Pin to new prerelease version of install tool (#8270)

Author: dibarbet

test/vscodeLauncher.ts

@@ -30,7 +30,7 @@ export async function prepareVSCodeAndExecuteTests(
     // Rather than having to uninstall Dev Kit between different test runs, we use workspace settings
     // to control which extensions are active - and we always install Dev Kit.
     const extensionsToInstall = [
-        'ms-dotnettools.vscode-dotnet-runtime@2.3.2',
+        'ms-dotnettools.vscode-dotnet-runtime@2.3.4',
         'ms-dotnettools.csharp',
         'ms-dotnettools.csdevkit@1.16.6',
     ];