Fix detect.py --update list bug

[glenn-jocher]

Resolves #8776

🛠️ PR Summary

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🌟 Summary

Improved optimizer stripping for updating models in detect.py.

📊 Key Changes

• Modified strip_optimizer function call to only pass the first element of the weights list.

🎯 Purpose & Impact

• 🛠️ Purpose: Fixes an issue with the model update process, specifically addressing a SourceChangeWarning.
• 🚀 Impact: Ensures that the model update function works correctly, especially important for users who frequently update their models to improve performance or incorporate the latest features. This should lead to a smoother user experience with fewer error messages related to model updates. 📈