Update concurrency group for community label workflow

[adimoldovan]

Submission Review Guidelines:

• I have followed the WooCommerce Contributing Guidelines and the WordPress Coding Standards.
• I have checked to ensure there aren't other open Pull Requests for the same update/change.
• I have reviewed my code for security best practices.

Changes proposed in this Pull Request:

Closes #47179

Updated the concurrency group for the community-label.yml workflow to use an unique group. The github.ref is always returning refs/heads/trunk incorrectly cancelling some runs.

I also checked for other workflows using issues or pull_request_target triggers but no other was using concurrency.

How to test the changes in this Pull Request:

Using the WooCommerce Testing Instructions Guide, include your detailed testing instructions:

After merge, open two issues at the same time. The Add Community Label, Assign Reviewers should run for both, the first run should not be cancelled by the second one.
Repeat the same test with two pull requests.

[github-actions]

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[rrennick]

I just had the one question about simplifying the change.

[rrennick]

@adimoldovan Could github.ref be replaced with github.head_ref to get the PR branch instead of trunk?

[adimoldovan]

It would help if we only had the pull_request_target event, but we also have the issues event for which github.head_ref is undefined.
On the other hand the group could be simpler in our case, because we only have the opened action for both events. I went with a group that would cover more actions in case they would be added later.
I guess we could go with the shorter community-label-${{ github.event_name == 'pull_request_target' && github.head_ref || github.run_id }}.

What do you think?

[rrennick]

That makes sense. Looks good as is.

[github-actions]

Hi @rrennick,

Apart from reviewing the code changes, please make sure to review the testing instructions as well.

You can follow this guide to find out what good testing instructions should look like:
https://github.com/woocommerce/woocommerce/wiki/Writing-high-quality-testing-instructions

[rrennick]

Looks good.