title: Ngrx Effects How to get the payload of the previous action
body: <p>If you've the following effect</p>
  <pre><code>  testEffects$ = createEffect(() =&gt; this.actions$.pipe(
      ofType(RDX_TEST_INC_VALUE),
      switchMap(ac =&gt; instance.get('/api/test/kam').then(res =&gt; {
        return {
          type: RDX_TEST_INC_VALUE_SUCCESS,
        }
      }).catch((err: AxiosError) =&gt; {
        return {
          type: RDX_TEST_INC_VALUE_ERROR,
        }
      }))
    ))
  </code></pre>
  <p>How do we return the payload of <code>RDX_TEST_INC_VALUE</code> with <code>RDX_TEXT_INC_VALUE_SUCCESS</code>?</p>