Update GitHub Actions workflow dependencies.

Change Summary

This update involves modifications to the GitHub Actions workflows deploy.yml and plan.yml. The primary changes are the pinning of specific commit hashes for GitHub Actions instead of using version tags. This ensures that the workflows use exact versions of the actions, potentially improving stability and reproducibility.

Technical Details

• Files Modified: .github/workflows/deploy.yml and .github/workflows/plan.yml
• Actions Updated:
  • actions/checkout updated from v4 to commit 34e114876b0b11c390a56381ad16ebd13914f8d5
  • gruntwork-io/terragrunt-action updated from v3 to commit 95fc057922e3c3d4cc021a81a213f088f333ddef
  • aws-actions/configure-aws-credentials updated from v5.1.1 to commit 61815dcd50bd041e203e49132bacad1fd04d2708
  • tailscale/github-action updated from v4 to commit 53acf823325fe9ca47f4cdaa951f90b4b0de5bb9

Key Learnings & Insights

• Stability through Specific Commits: Pinning actions to specific commit hashes rather than version tags can prevent unexpected changes due to new releases. This approach ensures that the CI/CD pipeline remains consistent across different runs.
• Version Control Best Practices: Using exact commit hashes is a best practice for critical workflows to avoid disruptions caused by updates in action repositories.
• Maintainability: While pinning to specific commits can offer stability, it also requires manual updates to adopt new features or security patches. A balance must be struck between stability and maintainability.

Impact Assessment

• Performance: There should be no direct performance impact since the actions themselves haven’t changed, only the method of referencing them.
• Security: Pinning to specific commits can enhance security by avoiding automatic updates that might introduce vulnerabilities.
• Maintainability: Future updates to these actions will require manual intervention to incorporate new changes or fixes.

Developer Notes

• Gotchas: Remember to update the pinned commit hashes when new versions of the actions are released to incorporate bug fixes or new features.
• Edge Cases: Ensure that the specified commits are compatible with the rest of the workflow to avoid runtime errors.
• Future Improvements: Consider implementing a process to regularly review and update the pinned commit hashes to benefit from the latest improvements while maintaining control over the CI/CD pipeline.