Automatic merge from submit-queue
federation: Adding support for namespace admission controls in federation-apiserver
Now that we have namespaces in federation apiserver, we can support namespace admission controls.
There are 3 of these:
namespace/autoprovision, namespace/exists and namespace/lifecycle.
namespace/autoprovision, namespace/exists should be deprecated in kubernetes(https://github.com/kubernetes/kubernetes/issues/31195). Adding support for namespace/lifecycle to federation-apiserver.
As in kube-apiserver, enabling namespace/lifecycle by default.
```release-note
Action required: If you have a running federation control plane, you will have to ensure that for all federation resources, the corresponding namespace exists in federation control plane.
federation-apiserver now supports NamespaceLifecycle admission control, which is enabled by default. Set the --admission-control flag on the server to change that.
```
cc @kubernetes/sig-cluster-federation @quinton-hoole