fix(release): gate canary releases on PR label

[jonrohan]

Updates the release-canary job in the Release workflow so that canary releases are opt-in via a "Canary Release" label on a PR, rather than running on every branch push.

Changes:

• Added pull_request: types: [labeled, synchronize] trigger to the workflow
• release-canary now only runs when:
  • The "Canary Release" label is applied to a PR, or
  • A new commit is pushed to a PR that already has the "Canary Release" label
• release-main and release-candidate are gated with github.event_name != 'pull_request' so they skip PR label events
• Checkout uses github.event.pull_request.head.sha for the canary job to build the actual PR head commit

Changelog

New

Changed

• Canary releases are now opt-in via the "Canary Release" PR label instead of running on every branch push

Removed

Rollout strategy

• Patch release
• Minor release
• Major release; if selected, include a written rollout or migration plan
• None; if selected, include a brief description as to why

This is a CI workflow change only — no package code is modified.

Testing & Reviewing

• Verify that pushing to main still triggers only release-main
• Verify that pushing to changeset-release/main still triggers only release-candidate
• Verify that applying the "Canary Release" label to a PR triggers release-canary
• Verify that pushing to a labeled PR re-triggers release-canary
• Verify that pushing to a branch (without a labeled PR) does not trigger any release job

Merge checklist

• Added/updated tests
• Added/updated documentation
• Added/updated previews (Storybook)
• Changes are SSR compatible
• Tested in Chrome
• Tested in Firefox
• Tested in Safari
• Tested in Edge
• (GitHub staff only) Integration tests pass at github/github-ui

[changeset-bot]

⚠️ No Changeset found

Latest commit: 211680b

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

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[Copilot]

Pull request overview

Updates the Release GitHub Actions workflow so canary publishing is opt-in via a “Canary Release” PR label, while ensuring main and candidate releases don’t run for PR label/sync events.

Changes:

• Add pull_request triggers (labeled, synchronize) to support label-driven canary runs.
• Gate release-canary on label presence and check out the PR head SHA for builds.
• Prevent release-main and release-candidate from running on pull_request events.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
.github/workflows/release.yml	Adds PR triggers and job-level if: gating so canary runs only when labeled; main/candidate skip PR events; canary checks out PR head SHA.
.github/pull_request_template.md	Documents how to trigger a canary release via the “Canary Release” label.

Comments suppressed due to low confidence (1)

.github/workflows/release.yml:126

• actions/checkout is using ref: ${{ github.event.pull_request.head.sha }} but doesn’t set repository:. For forked PRs that commit SHA usually isn’t in github.repository, so checkout will fail unless you also set with.repository: ${{ github.event.pull_request.head.repo.full_name }} (or ensure the job never runs for forks).

      - name: Checkout repository
        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd
        with:
          ref: ${{ github.event.pull_request.head.sha }}
          # This makes Actions fetch all Git history so that Changesets can generate changelogs with the correct commits

[siddharthkp]

Would be good to recommend this label in https://github.com/primer/react/blob/main/.github/workflows/recommend-integration-tests.yml as well