Create merge-main-into-prs.yml

[glenn-jocher]

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Introducing automated merging of the main branch into open PRs for seamless updates! 🚀

📊 Key Changes

• New GitHub action workflow: Merges the main branch into all open pull requests (PRs) automatically.
• Action is triggered manually via workflow_dispatch for now. This means it doesn't automatically run on any push to the main branch unless manually initiated.
• Uses Python script and GitHub's Python library (PyGithub) to handle the merge process.
• The workflow runs on the latest Ubuntu environment with Python 3.11.

🎯 Purpose & Impact

• Keep PRs Up-to-Date: Automatically updating PRs with the latest main branch changes reduces conflicts and ensures PRs are always compatible with the main branch.
• Saves Time: Automates the tedious and time-consuming process of manually keeping PRs up-to-date, allowing developers to focus on code quality and new features.
• Increased Workflow Efficiency: By ensuring all PRs are current, the mergeability of each PR is improved, streamlining the review and integration workflow.
• Potential Impact: Initially, this action is manually triggered, limiting its immediate impact. However, it lays the groundwork for automatic, seamless updates to PRs, significantly benefiting ongoing and future development processes.