MapboxGL.js script and css tag version too old for current studio maps. #68

<script src='https://api.tiles.mapbox.com/mapbox-gl-js/v2.11.0/mapbox-gl.js'></script>
<link href='https://api.tiles.mapbox.com/mapbox-gl-js/v2.11.0/mapbox-gl.css' rel='stylesheet' />

in index.html needs to be updated to

<script src='https://api.tiles.mapbox.com/mapbox-gl-js/v3.7.0/mapbox-gl.js'></script>
<link href='https://api.tiles.mapbox.com/mapbox-gl-js/v3.7.0/mapbox-gl.css' rel='stylesheet' />

so that current mapbox studio maps will work with it. With 2.11.0, I could load streets v11 but my map I had just created showed up blank. Changing the version to 3.7.0 (current listed in documentation for MapboxGL) fixed the issue immediately.