Automatic merge from submit-queue
[client-gen]Add Patch to clientset
* add the Patch() method to the clientset.
* I have to rename the existing Patch() method of `Event` to PatchWithEventNamespace() to avoid overriding.
* some minor changes to the fake Patch action.
cc @Random-Liu since he asked for the method
@kubernetes/sig-api-machinery
ref #26580
```release-note
Add the Patch method to the generated clientset.
```
Automatic merge from submit-queue
Implement the cluster-controller of kubernetes federation
This PR is the cluster-controller of kubernetes federation.
This controller of federation phase 1 just collect the status of federated clusters.
