on
          Called when a MapboxCarMapSurface has been detached from this observer. Some examples that can cause this to detach are:
- MapboxCarMap lifecycle is destroyed 
- This observer has been unregistered with MapboxCarMap.unregisterObserver 
You can assume that there was a corresponding call to onAttached with the same MapboxCarMapObserver instance.
Parameters
mapbox
loaded and ready car map surface