Fix autobuild.yml to build merges and PRs on release/* branches

[pljones]

Short description of changes

1. Adds release/** pattern to on.push.branches and on.pull_request.branches.
2. Makes the quoting consistent

CHANGELOG: SKIP

Context: Fixes an issue?

Direct merges to release/* or PRs to release/* would not have triggered the autobuild workflow as expected.

Does this change need documentation? What needs to be documented and how?

No.

Status of this Pull Request

I got Github CoPilot in VSCode to review it for me (it also did the quote fixes).

(Github CoPilot in VSCode GPT-5.3-Codex, 14.6 credits...)

What is missing until this pull request can be merged?

Human review.

I have no idea whether this needs backporting or whether it'll just work, either.

Checklist

• I've verified that this Pull Request follows the general code principles
• I tested my code and it does what I want
• My code follows the style guide
• I waited some time after this Pull Request was opened and all GitHub checks completed without errors.
• I've filled all the content above

[Copilot]

Pull request overview

Updates the autobuild.yml GitHub Actions workflow triggers so the autobuild pipeline runs for both direct pushes/merges and pull requests targeting release/* branches, aligning CI behavior with the release branching model.

Changes:

• Add release/** to on.push.branches so pushes/merges to release branches trigger autobuild.
• Add release/** to on.pull_request.branches so PRs targeting release branches trigger autobuild.
• Standardize quoting of branch/tag patterns for consistency.

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[ann0see]

Test it on your repo.

[ann0see]

And yes, it might need a backport.

[mcfnord]

MY LLM WROTE:

On the backporting question: it needs it. push runs the workflow file from the pushed branch, and pull_request runs it from the base branch — so release/3_12 needs its own copy either way; merging to main won't cover it.

Consistent with what's there now: every Auto-Build run on release/3_12 is workflow_dispatch, while Verify translations does fire on push to that branch — which it can only do because the branch carries its own copy of the filter.