`findStreetsSource` causes `setLanguage` to fail

[tsmock]

findStreetsSource should check the actual version instead of the URL.

It fails with bright-v9 (https://api.mapbox.com/styles/v1/mapbox/bright-v9) and satellite-v9 (https://api.mapbox.com/styles/v1/mapbox/satellite-v9). Both styles are version: 8, but neither match the check (return url && url.indexOf('mapbox.mapbox-streets-v8') > -1 || /mapbox-streets-v[1-9][1-9]/.test(url);).

This check should probably be as follows:

return (style.version && style.version == 8) ||  (url && url.indexOf('mapbox.mapbox-streets-v8') > -1 || /mapbox-streets-v[1-9][1-9]/.test(url));