title: Is it possible to CHANGE the position of a Marker in @react-google-maps/api?
body: <p>I have an existing map that relies on using the <code>setPosition</code> function on a single instance of <code>Marker</code> in the v3 Google Maps API. I don't see an obvious way to invoke that function from the <code>Marker</code> component exported by <code>@react-google-maps/api</code>.</p>
  <p>I want to use the <code>onMouseOver</code> and <code>onMouseOut</code> events to show a marker with (summary) information about whatever feature the user is mousing over in a live Google map. The existing javascript site works fine -- it uses the <code>loadGeoJson</code> method to add about 3,500 features to the map.</p>
  <p>The documentation and examples show how to pass a <code>position</code> prop to the Marker instance in the <code>render</code> method, but that provides only a static marker location.</p>
  <p>In my current <code>javascript</code> code, I do the following while handling an <code>onMouseOver</code> event:</p>
  <pre><code>function mouseInToRegion(e) {
    //...
    dataMarker.setLabel({'text': 'some informative string'});
    dataMarker.setPosition(e.latLng);
    dataMarker.setVisible(true);
  }
  </code></pre>
  <p>In the above fragment, <code>dataMarker</code> is a reference to a single marker instance creating during map initialization (at load time).</p>
  <p>Not surprisingly, the <code>onMouseOut</code> handler does little more than call <code>dataMarker.setVisible(false)</code>.</p>
  <p>How do I accomplish the analogous behavior using <code>@react-google-maps/api</code>?</p>