Make board-validation PR comment posting non-blocking on restricted token permissions

[Copilot]

Validate Board Files was failing for reasons unrelated to board content validation: the PR comment step errored with Resource not accessible by integration when token permissions were limited (e.g., fork PR context). This change ensures enforcement is driven by validation results, not comment-posting permissions.

• Workflow reliability

  • Updated .github/workflows/board_pr_validation.yml so Post validation report as PR comment does not fail the job when GitHub API write access is unavailable.
  • Keeps report-commenting best-effort while preserving validation execution and failure gating behavior.

• Behavioral impact

  • Validation logic and fail criteria remain unchanged.
  • Only the comment publication path is made non-blocking.

- name: Post validation report as PR comment
  if: always()
  continue-on-error: true
  uses: actions/github-script@v7

[xilinxgitops]

Can one of the admins verify this patch?

[github-actions]

🔍 Board Pre-Validation Report

No board files (under boards/) were changed in this pull request.