Remove use strict directives in main vs code ts files (part 2)

We compile using the alwaysStrict flag so these directives are not needed

This part removes most `use strict` directives that are right after the file header

src/vs/workbench/api/node/extHostOutputService.ts

@@ -2,7 +2,6 @@
  *  Copyright (c) Microsoft Corporation. All rights reserved.
  *  Licensed under the MIT License. See License.txt in the project root for license information.
  *--------------------------------------------------------------------------------------------*/
-'use strict';
 
 import { MainContext, MainThreadOutputServiceShape, IMainContext, ExtHostOutputServiceShape } from './extHost.protocol';
 import * as vscode from 'vscode';