Revert "refactor: optimize plugins for angular treeshaking"

This reverts commit 8b53c04dc5.

src/@ionic-native/plugins/zoom/index.ts

@@ -84,9 +84,7 @@ import { Cordova, IonicNativePlugin, Plugin } from '@ionic-native/core';
   repo: 'https://github.com/zoom/zoom-sdk-ionic', // the github repository URL for the plugin
   platforms: ['Android', 'iOS'] // Array of platforms supported, example: ['Android', 'iOS']
 })
-@Injectable({
-  providedIn: 'root'
-})
+@Injectable()
 export class Zoom extends IonicNativePlugin {
 
   /**