title: ngrx effect's action not triggering reducer
body: <p>I have my Angular 5 code working without ngrx effect. After adding effect and send HTTP request, I can not trigger reducer to be invoked by an action. My effect is this. This console log is getting hit with the correct http response. </p>
  
  <pre><code>@Injectable()
  export class PropertyEffects {
  @Effect({dispatch: false})
  propertyFetch$: Observable&lt;Action&gt; = this.actions$//.pipe(
      .ofType(PropertyActions.FETCH_ALL_PROPERTIES)
      .switchMap(action =&gt;
         this.httpClient.get('https://yxalbf1t6l.execute-api.us-east-1.amazonaws.com/dev/todos').pipe(
              // If successful, dispatch success action with result
              map(data =&gt; {
                  console.log(`Success ${JSON.stringify(data)}, 0, 2)`);
                  return new PropertyActions.OpenAllProperties(data)
              })
      )
  ); 
  </code></pre>
  
  <p>My reducer for the OpenAllProperties action below was getting called correctly before using effect. With effect, its console log never gets hit.</p>
  
  <pre><code>case PropertyListActions.OPEN_ALL_PROPERTIES:
     console.log("in reducer, action.payload: " + JSON.stringify(action.payload,null,2))
          const openAllProperties = !state.openAllProperties;
          return {
              ...state,
              openAllProperties: openAllProperties
          }
  </code></pre>
  
  <p>Please help. thank you!</p>