Merge pull request #50631 from luxas/kubeadm_dryrun_apiclient

Automatic merge from submit-queue (batch tested with PRs 47896, 50678, 50620, 50631, 51005)

kubeadm: Adds dry-run support for kubeadm using the `--dry-run` option

**What this PR does / why we need it**:

Adds dry-run support to kubeadm by creating a fake clientset that can get totally fake values (like in the init case), or delegate GETs/LISTs to a real API server but discard all edits like POST/PUT/PATCH/DELETE

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #

fixes: https://github.com/kubernetes/kubeadm/issues/389

**Special notes for your reviewer**:

This PR depends on https://github.com/kubernetes/kubernetes/pull/50626, first three commits are from there
This PR is a dependency for https://github.com/kubernetes/kubernetes/pull/48899 (kubeadm upgrades)

I have some small things to fixup and I'll yet write unit tests, but PTAL if you think this is going in the right direction

**Release note**:

```release-note
kubeadm: Adds dry-run support for kubeadm using the `--dry-run` option
```
cc @kubernetes/sig-cluster-lifecycle-pr-reviews @kubernetes/sig-api-machinery-pr-reviews

Kubernetes-commit: d852b8aad9397f530967b2b310a87966eb8b7e87

testing/actions.go

@@ -319,6 +319,17 @@ type DeleteAction interface {
 	GetName() string
 }
 
+type DeleteCollectionAction interface {
+	Action
+	GetListRestrictions() ListRestrictions
+}
+
+type PatchAction interface {
+	Action
+	GetName() string
+	GetPatch() []byte
+}
+
 type WatchAction interface {
 	Action
 	GetWatchRestrictions() WatchRestrictions