chore: Update outdated GitHub Actions versions

[pgoslatara]

Summary

This PR updates outdated GitHub Action versions. Specifically, it upgrades actions/setup-python from v4 to v6, actions/stale from v8 to v10, and actions/checkout from v3 to v6 to ensure compatibility with modern workflows and improved functionality.

Motivation

Upgrading to newer GitHub Actions versions ensures that the cookbook remains aligned with the latest tools and features, enhancing reliability and performance. These changes address outdated dependencies that may no longer support current workflows or introduce potential issues in automation processes.

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For new content

• I have added a new entry in registry.yaml so that my content renders on the cookbook website.
• I have conducted a self-review of my content based on the contribution guidelines:
  • Relevance: This content is related to building with OpenAI technologies and is useful to others.
  • Uniqueness: I have searched for related examples in the OpenAI Cookbook, and verified that my content offers new insights or unique information compared to existing documentation.
  • Spelling and Grammar: I have checked for spelling or grammatical mistakes.
  • Clarity: I have done a final read-through and verified that my submission is well-organized and easy to understand.
  • Correctness: The information I include is correct and all of my code executes successfully.
  • Completeness: I have explained everything fully, including all necessary references and citations.