Reference: https://github.com/kubernetes/kubernetes/pull/44771
Fixes https://github.com/kubernetes/minikube/issues/1252
TPRs are incorrectly coupled with the RestMapper right now. The real
solution is for TPRs to not register themselves with the RestMapper.
This is a short term patch for minikube until the work is done
upstream. On start/stop, the namespace controller and the garbage
collector controller both call this code and panic since TPRs have
registered themselves with enabled versions but have no group metadata.
Matt Rickard