Bump mapbox-gl from 1.3.1 to 1.6.1

Bumps [mapbox-gl](https://github.com/mapbox/mapbox-gl-js) from 1.3.1 to 1.6.1. - [Release notes](https://github.com/mapbox/mapbox-gl-js/releases) - [Changelog](https://github.com/mapbox/mapbox-gl-js/blob/master/CHANGELOG.md) - [Commits](mapbox/mapbox-gl-js@v1.3.1...v1.6.1) Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Author: dependabot-preview[bot]

package.json

@@ -124,7 +124,7 @@
  "leaflet": "1.5.1",
  "lodash.remove": "^4.7.0",
  "lodash.topairs": "4.3.0",
- "mapbox-gl": "1.3.1",
+ "mapbox-gl": "1.6.1",
  "mapv": "2.0.40",
  "ol": "6.1.1",
  "pbf": "3.0.2",