Update CONTRIBUTING.md

CONTRIBUTING.md

@@ -45,6 +45,11 @@ Run this after you have finalized your changes and make sure there are no errors
 npm run build
 ```
 
+## Previewing the built dist directory locally
+```bash
+serve -s dist
+```
+
 ## Lints and fixes files
 This runs a static code analysis and you should make sure there are no warnings or errors.
 ```bash