Automatic merge from submit-queue
Align Extender's validation with prioritizers.
**What this PR does / why we need it**:
Align Extender's validation with prioritizers.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes # N/A
**Release note**:
```release-note-none
```