Update: Read API Hostname from LocalStorage

based on the implementation from coscine/frontend/libraries/api-client!99 (comment 2458307)

src/CodeGen/CodeGenerator/CoscineCodeGenerator.cs

@@ -90,6 +90,10 @@ if (typeof window !== 'undefined') {
 }
 
 const getHostName = () => {
+  const localStorageHostName = typeof window !== 'undefined' ? localStorage.getItem('coscine.api.hostname') : null;
+  if (localStorageHostName) {
+    return localStorageHostName;
+  }
   let hostName = typeof window !== 'undefined' ? window.location.hostname : 'coscine.rwth-aachen.de';
   if (hostName.indexOf(':') !== -1) {
     if (hostName.indexOf('https://') !== -1) {
@@ -103,4 +107,4 @@ const getHostName = () => {
 ";
         return Task.FromResult(combinationFileText);
     }
-}
\ No newline at end of file
+}