title: TypeScript, react testing missing type in AnyAction
body: <p>I'm having this error:</p>
  <pre><code>TS2345: Argument of type '(dispatch: Dispatch) =&gt; Promise&lt;void&gt;' is not assignable to parameter of
  type 'AnyAction'.   Property 'type' is missing in type '(dispatch: Dispatch) =&gt; Promise&lt;void&gt;' but
  required in type 'AnyAction'. type' is declared here* :
  </code></pre>
  <p><code>*</code> The code of the declaration is:</p>
  <pre><code>export interface Action&lt;T = any&gt; {
    type: T
  }
  </code></pre>
  <p>AnyAction extends Action.</p>
  <p>This is my code on the test:</p>
  <pre><code>import configureStore from 'redux-mock-store';
  import reduxThunk from 'redux-thunk';
  // some code, then in the test I have:
  
  const mockStore = configureStore([reduxThunk]);
  const store = mockStore({});
  
  store.dispatch(signIn()); //here I have the error
  </code></pre>
  <p>The definition of <code>signIn</code> is:</p>
  <pre><code>export const signIn = () =&gt;
    async (dispatch: Dispatch): Promise&lt;void&gt; =&gt; {
      dispatch({
        type: SIGN_IN_REQUEST
      });
    };
  </code></pre>
  <p>Any hint or idea on how to fix it?</p>