move main thread task to browser (#70319) (#70940)

src/vs/workbench/api/electron-browser/extensionHost.contribution.ts

@@ -51,7 +51,7 @@ import '../browser/mainThreadUrls';
 import '../browser/mainThreadWindow';
 import '../browser/mainThreadWorkspace';
 import './mainThreadComments';
-import './mainThreadTask';
+import '../browser/mainThreadTask';
 import './mainThreadWebview';
 import 'vs/workbench/api/node/apiCommands';