title: Why am I getting the error message "Property 'then' does not exist on type 'AsyncThunkAction'"?
body: <p>I can't seem to receive a <code>Promise</code> from <code>createAsyncThunk</code> function from <code>Redux-toolkit</code>
  I'm fairly new to Typescript and I'm struggling to figure out why it's giving me
  <code>Property 'then' does not exist on type 'AsyncThunkAction&lt;Student, number, {}&gt;'</code> error even though the promise does get returned if I remove the typing.
  Here is my <code>createAsyncThunk</code> f-n</p>
  <pre><code>export const getStudentByIdRequest = createAsyncThunk&lt;Student, number&gt;(
    'student/getStudentByIdRequest',
    async (id, { rejectWithValue }) =&gt; {
      try {
        const { data } = await instance.get(`student/${id}/`)
        return data
      } catch (err) {
        let error: AxiosError = err
        if (error) {
          return rejectWithValue({
            message: `Error. Error code ${error.response?.status}`,
          })
        }
        throw err
      }
    }
  )
  </code></pre>
  <p>And that is how I dispatch it from my <code>React</code> component</p>
  <pre><code>dispatch(getStudentByIdRequest(userId)).then((res) =&gt; console.log(res))
  </code></pre>
  <p>The error appears where I try to call <code>then</code> on the thunk</p>