refactor: optimize plugins for angular treeshaking

BREAKING CHANGE: You can remove the plugin import from the app.module.ts because of the changed Inject decorator

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

@@ -78,7 +78,9 @@ export interface TealConfig {
   platforms: ['Android', 'iOS'], // Array of platforms supported, example: ['Android', 'iOS']
   install: '' // OPTIONAL install command, in case the plugin requires variables
 })
-@Injectable()
+@Injectable({
+  providedIn: 'root'
+})
 export class Tealium extends IonicNativePlugin {
   /**
    * This function initializes the Tealium Cordova plugin.