Fix check_requirements() resource warning allocation open file

[ayman-saleh]

The file.open usage was throwing ResourceWarning Exceptions within our internal testing framework, tracked down to the unclosed file handler while checking the requirements.txt file.

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Improvement in handling requirements file parsing in utils/general.py.

📊 Key Changes

• Shift from a direct file open approach to utilizing a context manager for reading requirements.txt.

🎯 Purpose & Impact

• Purpose: Ensure that the requirements file is properly closed after its contents are read, which adheres to best coding practices and avoids potential resource leaks.
• Impact: This update results in cleaner code and more reliable resource management, but it should not affect the functionality from the user's perspective. Maintainers and developers, however, will benefit from code that is more robust and maintainable. 👍🔒

[github-actions]

👋 Hello @ayman-saleh, thank you for submitting a 🚀 PR! To allow your work to be integrated as seamlessly as possible, we advise you to:

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[glenn-jocher]

@ayman-saleh good catch! Thanks for the PR.