Dont install extension during test runs

For some reason, the extension `justusadam.language-haskell` can't be
found any more on windows.
As we need to do a release, we ignore this issue for now and just do not
require the extension to be installed for the test suite.

Author: fendor

test/runTest.ts

@@ -21,7 +21,7 @@ async function main() {
     );
 
     // We have to install this dependant extension
-    installExtension(vscodeExecutablePath, 'justusadam.language-haskell');
+    // installExtension(vscodeExecutablePath, 'justusadam.language-haskell');
 
     // The folder containing the Extension Manifest package.json
     // Passed to `--extensionDevelopmentPath`