Base class for the server implementation of the service GkeHub.
The GKE Hub service handles the registration of many Kubernetes clusters to
Google Cloud, and the management of multi-cluster features over those
clusters.
The GKE Hub service operates on the following resources:
* [Membership][google.cloud.gkehub.v1.Membership]
* [Feature][google.cloud.gkehub.v1.Feature]
GKE Hub is currently available in the global region and all regions in
https://cloud.google.com/compute/docs/regions-zones. Feature is only
available in global region while membership is global region and all the
regions.
**Membership management may be non-trivial:** it is recommended to use one
of the Google-provided client libraries or tools where possible when working
with Membership resources.