title: ngrx effects called multiple times after it return the value
body: <p>ngrx effects called multiple times after it return the value.</p>
  
  <pre><code>loadMovies$: Observable&lt;Action&gt; = createEffect(() =&gt; {
      return this.actions$.pipe(
      ofType(counterActions.CounterActionTypes.IncrementCounter),
      flatMap(() =&gt; {
          return this.userService.counter()
          .pipe(
            map(movies =&gt; {
               return new counterActions.IncrementCounter();
            }));
        }
      ));
    });
  </code></pre>