371: Update tiny_http requirement from 0.11 to 0.12 r=mkroening a=dependabot[bot]

Updates the requirements on [tiny_http](https://github.com/tiny-http/tiny-http) to permit the latest version.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a href="https://github.com/tiny-http/tiny-http/releases">tiny_http's releases</a>.</em></p>
<blockquote>
<h2>0.12.0</h2>
<ul>
<li>
<p>Bumped the minimum compiler version tested by CI to 1.56 - this is necessary due to an increasing number of dependencies introducing Cargo manifest features only supported on newer versions of Rust.</p>
</li>
<li>
<p><a href="https://github-redirect.dependabot.com/tiny-http/tiny-http/pull/224">Add support for UNIX sockets</a>
Thanks to <a href="https://github.com/ColonelThirtyTwo"><code>`@​ColonelThirtyTwo</code></a>` for adding support for binding to UNIX sockets when creating a tiny-http server. This change makes a few small breaking API modifications, if you are constructing <code>ServerConfig</code> manually you will need to use the new <code>ListenAddr</code> type rather than directly supplying a <code>net::SocketAddr</code>. Likewise <code>Server::server_addr()</code> will now return an enum that can represent either a TCP socket or a UNIX socket.</p>
<p>Finally <code>Request::remote_addr()</code> now returns an <code>Option&lt;&amp;SocketAddr&gt;</code> as UNIX sockets don't ever have a remote host.</p>
</li>
<li>
<p><a href="https://github-redirect.dependabot.com/tiny-http/tiny-http/pull/228">Reduce required dependencies by switching to <code>httpdate</code></a>
<a href="https://github.com/esheppa"><code>`@​esheppa</code></a>` replaced our internal HTTPDate type with the <code>httpdate</code> library (used extensively in the community by Hyper, Tokio and others) which reduces our baseline dependency tree from 18 crates to 5!</p>
</li>
<li>
<p><code>TestRequest::path</code> no longer has a <code>'static</code> bound, allowing for fuzzers to generate test request paths at runtime.</p>
</li>
<li>
<p>Unpinned <code>zeroize</code> so it can float around any stable <code>^1</code> version.</p>
</li>
</ul>
<h2>New Contributors</h2>
<ul>
<li><a href="https://github.com/ColonelThirtyTwo"><code>`@​ColonelThirtyTwo</code></a>` made their first contribution in <a href="https://github-redirect.dependabot.com/tiny-http/tiny-http/pull/224">tiny-http/tiny-http#224</a></li>
<li><a href="https://github.com/nhynes"><code>`@​nhynes</code></a>` made their first contribution in <a href="https://github-redirect.dependabot.com/tiny-http/tiny-http/pull/226">tiny-http/tiny-http#226</a></li>
<li><a href="https://github.com/ruuda"><code>`@​ruuda</code></a>` made their first contribution in <a href="https://github-redirect.dependabot.com/tiny-http/tiny-http/pull/225">tiny-http/tiny-http#225</a></li>
<li><a href="https://github.com/esheppa"><code>`@​esheppa</code></a>` made their first contribution in <a href="https://github-redirect.dependabot.com/tiny-http/tiny-http/pull/228">tiny-http/tiny-http#228</a></li>
</ul>
<p><strong>Full Changelog</strong>: <a href="https://github.com/tiny-http/tiny-http/compare/0.11.0...0.12.0">https://github.com/tiny-http/tiny-http/compare/0.11.0...0.12.0</a></p>
</blockquote>
</details>
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a href="https://github.com/tiny-http/tiny-http/blob/master/CHANGELOG.md">tiny_http's changelog</a>.</em></p>
<blockquote>
<h2>0.12.0</h2>
<ul>
<li>
<p>Bumped the minimum compiler version tested by CI to 1.56 - this is necessary due to an increasing number of dependencies
introducing Cargo manifest features only supported on newer versions of Rust.</p>
</li>
<li>
<p><a href="https://github-redirect.dependabot.com/tiny-http/tiny-http/pull/224">Add support for UNIX sockets</a></p>
<p>Thanks to <a href="https://github.com/ColonelThirtyTwo"><code>`@​ColonelThirtyTwo</code></a>` for adding support for binding to UNIX sockets when creating a tiny-http server. This change
makes a few small breaking API modifications, if you are constructing <code>ServerConfig</code> manually you will need to use the new <code>ListenAddr</code>
type rather than directly supplying a <code>net::SocketAddr</code>. Likewise <code>Server::server_addr()</code> will now return an enum that can
represent either a TCP socket or a UNIX socket.</p>
<p>Finally <code>Request::remote_addr()</code> now returns an <code>Option&lt;&amp;SocketAddr&gt;</code> as UNIX sockets don't ever have a remote host.</p>
</li>
<li>
<p><a href="https://github-redirect.dependabot.com/tiny-http/tiny-http/pull/228">Reduce required dependencies by switching to <code>httpdate</code></a></p>
<p><a href="https://github.com/esheppa"><code>`@​esheppa</code></a>` replaced our internal HTTPDate type with the <code>httpdate</code> library (used extensively in the community by Hyper, Tokio and others)
which reduces our baseline dependency tree from 18 crates to 5!</p>
</li>
<li>
<p><code>TestRequest::path</code> no longer has a <code>'static</code> bound, allowing for fuzzers to generate test request paths at runtime.</p>
</li>
<li>
<p>Unpinned <code>zeroize</code> so it can float around any stable <code>^1</code> version.</p>
</li>
</ul>
<h2>0.11.0</h2>
<ul>
<li>
<p><a href="https://github-redirect.dependabot.com/tiny-http/tiny-http/pull/218">Add support for Rustls</a></p>
<p>Thanks to <a href="https://github.com/3xmblzj5"><code>`@​3xmblzj5</code></a>` and <a href="https://github.com/travispaul"><code>`@​travispaul</code></a>` for their help in implementing <a href="https://github.com/rustls/rustls"><code>Rustls</code></a> as a
drop-in replacement for OpenSSL, you can now build <code>tiny-http</code> with TLS support without any external dependencies!
OpenSSL will remain the default implementation if you just enable the <code>ssl</code> feature, but you are strongly encouraged
to use <code>ssl-rustls</code> where possible!</p>
</li>
<li>
<p><a href="https://github.com/tiny-http/tiny-http/commit/876efd6b752e991c699d27d3d0ad9a47e9d35c29">Fix incorrect certificate chain loading</a></p>
<p>Fix a longstanding bug where we were only loading the first (i.e. the leaf) certificate from any PEM file supplied by
the user.</p>
</li>
</ul>
<h2>0.10.0</h2>
<ul>
<li>
<p><a href="https://github.com/tiny-http/tiny-http/commit/75ac7758fd0ca660c35f58c2a36edb23a42cda32">Replace chrono with time-rs</a></p>
<p><code>chrono</code> was only used to store and format <code>DateTime</code> into the slightly odd format required by RFC 7231, so to
avoid the numerous RUSTSEC advisories generated by the <code>localtime_r</code> issue, we can just drop it entirely and switch
to <code>time-rs</code>.
Unfortunately this means we need to <strong>bump our minimum tested compiler version to 1.51</strong>, and as such this change
requires a full minor release.</p>
</li>
</ul>
<h2>0.9.0</h2>
<ul>
<li><a href="https://github-redirect.dependabot.com/tiny-http/tiny-http/pull/208">Rust 2018 Refactor</a></li>
</ul>
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</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="https://github.com/tiny-http/tiny-http/commit/212b1c45852fef2093dc1374875a9393c55eb4b9"><code>212b1c4</code></a> Prepare for 0.12.0 release</li>
<li><a href="https://github.com/tiny-http/tiny-http/commit/87b00a8b32996f72b86a10082cf665f4e4520ba3"><code>87b00a8</code></a> Merge pull request <a href="https://github-redirect.dependabot.com/tiny-http/tiny-http/issues/228">#228</a> from esheppa/use-httpdate</li>
<li><a href="https://github.com/tiny-http/tiny-http/commit/c2a38adb0411ff81b3323d8b59af01994b77f035"><code>c2a38ad</code></a> remove unused url dependency, switch to httpdate</li>
<li><a href="https://github.com/tiny-http/tiny-http/commit/f0fce7ed0bdf7439b5bd0b2d15fa82944aac30f6"><code>f0fce7e</code></a> Remove the 'static requirement on TestRequest::path</li>
<li><a href="https://github.com/tiny-http/tiny-http/commit/dd9c8dd6ac31c13753048bbb9e9b0b9a2710503e"><code>dd9c8dd</code></a> Use ^1 zeroize</li>
<li><a href="https://github.com/tiny-http/tiny-http/commit/b9d9e8a9fe3ee1e03eceb003a3a3f999ea291535"><code>b9d9e8a</code></a> Update log dependency to 0.4.4</li>
<li><a href="https://github.com/tiny-http/tiny-http/commit/789e1c1102efdd241bdf643bc74d52bb9c1b63e3"><code>789e1c1</code></a> Add support for UNIX sockets</li>
<li>See full diff in <a href="https://github.com/tiny-http/tiny-http/compare/0.11.0...0.12.0

">compare view</a></li>
</ul>
</details>
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