Create SECURITY.md

[pablorq]

Can you please enable the 'issues' tab?

Background

Changes

Documentation

Test Plan

PR Quality Checklist

• [ ] My pull request is atomic and focuses on a single change.
• [ ] I have thoroughly tested my changes with multiple different prompts.
• [ ] I have considered potential risks and mitigations for my changes.
• [ ] I have documented my changes clearly and comprehensively.
• [ ] I have not snuck in any "extra" small tweaks changes