Update pull-requests.json to skip CI in some cases

[rowlandgeoff]

Skip CI when only unrelated changes are made.

Closes: #457

[mergify]

This pull request does not have a backport label. Could you fix it @rowlandgeoff? 🙏
To fixup this pull request, you need to add the backport labels for the needed
branches, such as:

• backport-v./d./d is the label to automatically backport to the 1./d branch. /d is the digit
  NOTE: backport-skip has been added to this pull request.

[v1v]

Will this work with the required GH checks?

[rowlandgeoff]

Will this work with the required GH checks?

@v1v Good question. I branched off of this branch and opened a test PR to see if it would trigger this new flow, but it didn't. I think the pull-requests.json change must need to be merged before it can go into effect. Once this is merged, I can open a test PR soon after to verify it works.

Based on the current branch protection rules, I think I'll need to change the check source from Buildkite to any source. That's what I've seen needed in the elastic-agent repo.

Also, those other two required Buildkite checks can probably be removed, since they're sub-jobs of the main pipeline.

[v1v]

LGTM, let's see how the required checks do after merging it

[elasticmachine]

💚 Build Succeeded

• Buildkite Build
• Commit: f716153

History

• 💚 Build #579 succeeded 0fbd08f

cc @rowlandgeoff

[elasticmachine]

💚 Build Succeeded

• Buildkite Build
• Commit: f716153

History

• 💚 Build #579 succeeded 0fbd08f

cc @rowlandgeoff

[elasticmachine]

💚 Build Succeeded

• Buildkite Build
• Commit: f716153

History

• 💚 Build #680 succeeded 0fbd08f

cc @rowlandgeoff