check_git_status() bug fix

[glenn-jocher]

Fix for UnboundLocalError: local variable 's' referenced before assignment.

🛠️ PR Summary

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🌟 Summary

Improved messaging for code updates in the YOLOv5 project.

📊 Key Changes

• Updated the comment to suggest running 'git pull' in a more general context, not just for YOLOv5.
• Simplified error handling by printing the exception directly instead of converting it to a string and then printing.

🎯 Purpose & Impact

• The change to the recommendation language makes it applicable to more contexts, providing clearer guidance to users on how to keep their codebase up to date.
• Streamlining the error output makes the code cleaner and potentially easier for users to understand the nature of any issues they encounter.