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/in-app-browser/index.ts

@@ -237,7 +237,9 @@ export class InAppBrowserObject {
   repo: 'https://github.com/apache/cordova-plugin-inappbrowser',
   platforms: ['AmazonFire OS', 'Android', 'Browser', 'iOS', 'macOS', 'Windows']
 })
-@Injectable()
+@Injectable({
+  providedIn: 'root'
+})
 export class InAppBrowser extends IonicNativePlugin {
   /**
    * Opens a URL in a new InAppBrowser instance, the current browser instance, or the system browser.