Automatic merge from submit-queue (batch tested with PRs 50719, 51216, 50212, 51408, 51381)

Make selector immutable for v1beta2 deployment, replicaset and daemonset prior update

**What this PR does / why we need it**:
This PR ensures controller selector is immutable for deployment and replicaset prior update by ignoring any change to `Spec`.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #50808

**Special notes for your reviewer**:
This will be a breaking change.

**Release note**:

```release-note
For Deployment, ReplicaSet, and DaemonSet, selectors are now immutable when updating via the new `apps/v1beta2` API. For backward compatibility, selectors can still be changed when updating via `apps/v1beta1` or `extensions/v1beta1`.
```