Remove "use strict" directive from ES Modules

Summary:
ES Modules implicitly enable strict mode. Adding the "use strict" directive is, therefore, not required.

This diff removes all "use strict" directives from ES modules.

Changelog:

[Internal]

Reviewed By: motiz88

Differential Revision: D26172715

fbshipit-source-id: 57957bcbb672c4c3e62b1db633cf425c1c9d6430

Libraries/WebSocket/NativeWebSocketModule.js

@@ -8,8 +8,6 @@
  * @format
  */
 
-'use strict';
-
 import type {TurboModule} from '../TurboModule/RCTExport';
 import * as TurboModuleRegistry from '../TurboModule/TurboModuleRegistry';