Add local option to the label command

[asalkeld]

What this PR does / why we need it:
Add the --local option to be both consistent with other commands and so it can be used with "set selector" and "create service".

Which issue this PR fixes
Related: #7296

Special notes for your reviewer:
None

Release note:

Add a new option "--local" to the `kubectl label`

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This change is

[asalkeld]

This was split out of #28949

[deads2k]

@asalkeld Can you add a test to test-cmd.sh. Then lgtm.

[deads2k]

@asalkeld Can you add a test to test-cmd.sh. Then lgtm.

Oh, and while I'm thinking about it. kubectl annotate too? I'd expect them to be closely related. Can be a separate pull if you wish.

[asalkeld]

@deads2k I have added the test-cmd.sh test. I'll do the annotate one separately.

[k8s-ci-robot]

Jenkins unit/integration failed for commit c2b8377fd271e543783cfda467c1ac2ddbf4b31f. Full PR test history.

The magic incantation to run this job again is @k8s-bot unit test this. Please help us cut down flakes by linking to an open flake issue when you hit one in your PR.

[asalkeld]

@deads2k the annotate one is here: #34074

[deads2k]

lgtm

[k8s-github-robot]

@k8s-bot test this [submit-queue is verifying that this PR is safe to merge]

[k8s-github-robot]

Automatic merge from submit-queue