Automatic merge from submit-queue (batch tested with PRs 46775, 47009)

kuberuntime: check the value of RunAsNonRoot when verifying

The verification function is fixed to check the value of RunAsNonRoot,
not just the existence of it. Also adds unit tests to verify the correct
behavior.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #46996

**Release note**:

```release-note
Fix the bug where container cannot run as root when SecurityContext.RunAsNonRoot is false.
```