Fix Rerun Unstable Failures workflow: bind job to Official-Build environment

[Copilot]

The new Rerun Unstable Failures workflow (failed run) errored with [@octokit/auth-app] privateKey option is required, then Failed to fetch run because GH_TOKEN was empty.

secrets.PRIVATE_KEY is scoped to the Official-Build environment in this repo — every other workflow consuming it (SubmitStabilityJobs, UpdateBCArtifactVersion, UpdateALGoProjects, UpdatePackageVersions, UpdateGitHubGoSystemFiles) declares that environment on the job. This one did not, so the secret expanded to empty, the app-token action failed, and the secrets.RERUNPAT fallback was empty too.

Changes to .github/workflows/RerunUnstableFailures.yaml

• Add environment: Official-Build to the RerunUnstableFailures job so secrets.PRIVATE_KEY resolves.
• Drop the now-redundant if: vars.APP_ID != '', continue-on-error: true, and || secrets.RERUNPAT fallback so the wiring matches the other Official-Build workflows.

  RerunUnstableFailures:
    if: github.repository_owner == 'microsoft' && github.event.workflow_run.conclusion == 'failure'
    runs-on: ubuntu-slim
    environment: Official-Build
    ...
      - name: Create GitHub App Token
        id: app-token
        uses: actions/create-github-app-token@... # v3.1.1
        with:
          app-id: ${{ vars.APP_ID }}
          private-key: ${{ secrets.PRIVATE_KEY }}

      - name: Rerun unstable failures
        env:
          GH_TOKEN: ${{ steps.app-token.outputs.token }}

Fixes AB#632025

[Copilot]

Pull request overview

Fixes the Rerun Unstable Failures GitHub Actions workflow by ensuring it runs in the Official-Build environment so the GitHub App credentials resolve correctly and the workflow can mint a usable GH_TOKEN for rerun operations.

Changes:

• Bind the RerunUnstableFailures job to environment: Official-Build so secrets.PRIVATE_KEY is available.
• Remove the now-redundant guard/soft-failure behavior around GitHub App token creation.
• Remove the PAT fallback and rely exclusively on the GitHub App token output.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.