title: how can i use watchPositionAsync in useFocusEffect
body: <p><strong>i tried to use this code</strong></p>
  <pre><code>
      useFocusEffect(
          useCallback(() =&gt; {
              const getLocation = async() =&gt; {
                  await getPermissionsAsync()
                  const subscribe = await watchPositionAsync({
                  accuracy:Accuracy.BestForNavigation,
                  timeInterval:5000
                  },(location) =&gt; {console.log(1)})
                  return () =&gt; subscribe.remove()
              }
  
              return getLocation()
          }, [])
        );
      
  </code></pre>
  <p><strong>but i get this error</strong></p>
  <ul>
  <li>An effect function must not return anything besides a function, which is used for clean-up. It looks like you wrote 'useFocusEffect(async () =&gt; ...)' or returned a Promise. Instead, write the
  async function inside your effect and call it immediately:</li>
  <li></li>
  </ul>
  <pre><code> useFocusEffect(
     React.useCallback() =&gt; {
       async function fetchData() {
         // You can await here
       const response = await MyAPI.getData(someId);
         // ...
       }
  
       fetchData();
     }, [someId])
   };
  </code></pre>