Automatic merge from submit-queue
CRI: fix ImageStatus comment
**What this PR does / why we need it**:
GRPC cannot encode `nil` (CRI-O itself panic while trying to encode `nil` for `ImageStatus`). This PR fixes `ImageStatus` comment to say that when the image does not exist the call returns a response having `Image` set to `nil` (instead of saying implementors should return `nil` directly).
/cc @mrunalp @vishh @feiskyer
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
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Signed-off-by: Antonio Murdaca <runcom@redhat.com>
22db6c99a7