Use Google basemaps from Carto

Firstly, thanks for this awesome project!

**Is your feature request related to a problem? Please describe.**
I would like to use Google basemaps in lonboard from Carto (https://docs.carto.com/carto-for-developers/carto-for-react/guides/basemaps) e.g. GOOGLE_ROADMAP

**Describe the solution you'd like**
https://developmentseed.org/lonboard/latest/api/basemap/ lists the Google basemaps with instructions on how to pass creds through

**Describe alternatives you've considered**
I should probably figure out how to do this in carto first

**Additional context**
Nope