Fix: Update README contributors workflow to create pull request instead of pushing directly

[Copilot]

This PR modifies the update-readme-contributors.yml workflow to create a pull request instead of pushing changes directly to the main branch.

Changes:

• Replaced manual git commands with the peter-evans/create-pull-request action
• Added explicit permissions to the workflow to ensure it has the necessary access:
  • contents: write
  • pull-requests: write
• Configured the PR creation with:
  • Descriptive title and body
  • Unique branch name with timestamp suffix
  • Automatic branch deletion after merge

Benefits:

• Follows git best practices by not pushing directly to the main branch
• Enables code review before changes are merged
• Reduces the risk of unintended changes to the main branch
• Maintains a clear history of contributor updates

The workflow continues to run on the same schedule and triggers, but now creates a PR instead of directly modifying the main branch.

Fixes #129.

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[github-actions]

Overall Project	90.58%	🍏

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[github-actions]

Overall Project	90.58%	🍏

There is no coverage information present for the Files changed