docs: cite org-security and tag-validation references

[CybotTM]

Summary

Adds two previously orphaned reference files to the References table: org-security-settings.md (SHA pinning) and tag-validation.md (defense-in-depth). The reusable-workflow-security reference is already cited upstream.

Test plan

• Verify reference files exist and are reachable from SKILL.md

[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

None

[gemini-code-assist]

Code Review

This pull request updates the SKILL.md file by adding two new entries to the references table: one for organization-level security settings regarding SHA pinning and another for tag validation as a defense-in-depth measure. I have no feedback to provide as there were no review comments.

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[Copilot]

Pull request overview

Updates the GitHub Project skill documentation to include two existing but previously uncited reference documents in the SKILL.md “References” table, improving discoverability of security guidance.

Changes:

• Add a reference entry for references/org-security-settings.md (org-level security / SHA pinning).
• Add a reference entry for references/tag-validation.md (tag validation / defense-in-depth).

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud