Update notification mechansim for label CI checks

[Goldspear]

Fixes #88098

What Changed:

1. Check_labels CI job no longer fails, but only adding a comment prompt if the required labels is not satisfied.
2. Merge would fail with a comment instead if the required labels are not satisfied.

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[linux-foundation-easycla]

• ✅ login: Goldspear / name: Ning Xu (8b4d31e)
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[ZainRizvi]

This is looking really good! It just needs a couple more things:

1. Could you please add unit tests in .github/scripts/test_trymerge.py
2. We'll also want to remove the check_labels.py and move the corresponding unit tests from .github/workflows/check-labels.yml to test_trymerge.py
3. Remove the .github/workflows/check-labels.yml workflow

Your call on whether you'd like to do #2 & #3 as part of this PR or as a separate PR

[Goldspear]

Thanks @ZainRizvi for the prompt review and suggestions!

The original issue description suggested to keep the check_label CI job, hence the original PR, but I agree it's redundant and should be cleaned up. The new commit now has it removed and the relevant unit tests refractored accordingly. Please kindly take another look when you have a chance :)

[ZainRizvi]

Thanks @ZainRizvi for the prompt review and suggestions!

The original issue description suggested to keep the check_label CI job, hence the original PR, but I agree it's redundant and should be cleaned up. The new commit now has it removed and the relevant unit tests refractored accordingly. Please kindly take another look when you have a chance :)

Actually, thinking it over again I'd prefer the approach described in the ticket where the label message is still shared with devs earlier, but it doesn't turn into a red X failing the CI.

Would you mind putting it back in that format? Apologies for the churn

[Goldspear]

Actually, thinking it over again I'd prefer the approach described in the ticket where the label message is still shared with devs earlier, but it doesn't turn into a red X failing the CI.

Ah that makes sense, sure thing, I will add the check_label ci job back (in the new PR instead) for comment only. Most of the tests/moved fcns can stay where they are I think, so not much of a waste :)