message: fix(core): AsyncPipe now compatible with RxJS 7
  Adds a fix to make sure that RxJS v7 Observable is compatible with AsyncPipe. This is a typings-only change.
  For more information see:
  PR Close
diff: @@ -3,9 +3,9 @@ export declare const APP_BASE_HREF: InjectionToken<string>;
  export declare class AsyncPipe implements OnDestroy, PipeTransform {
  constructor(_ref: ChangeDetectorRef);
  ngOnDestroy(): void;
  - transform<T>(obj: Subscribable<T> | Promise<T>): T | null;
  + transform<T>(obj: Observable<T> | Subscribable<T> | Promise<T>): T | null;
  transform<T>(obj: null | undefined): null;
  - transform<T>(obj: Subscribable<T> | Promise<T> | null | undefined): T | null;
  + transform<T>(obj: Observable<T> | Subscribable<T> | Promise<T> | null | undefined): T | null;
  }
  export declare class CommonModule {
  