Skip test report check creation for fork PRs

[Copilot]

Description

The build (8.0.x) job failed after successful build, test, and CodeQL steps because dorny/test-reporter attempted to create a check run from a forked pull_request, where GITHUB_TOKEN cannot write checks.

• Root cause

  • Fork PR runs receive restricted token permissions.
  • The Test Report step requires checks: write at runtime to create the DotNet Tests check run.

• Change

  • Gate the Test Report step to run only when check creation is permitted:

    if: ${{ (success() || failure()) && (github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name == github.repository) }}

  • Same-repo PRs, pushes, schedules, and manual runs still publish test reports.
  • Fork PRs still build and test, but skip check-run publishing.

Checklist

• The code change is covered by unit tests. I have added tests that prove my fix is effective or that my feature works
• I have performed end-to-end test locally.
• New and existing unit tests pass locally with my changes
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I used clear names for everything
• I have performed a self-review of my own code