Update torch.cuda.amp to torch.amp

[jacobdbrown4]

torch.cuda.amp is deprecated as of Pytorch 2.4. This PR updates use to torch.amp. This gets rid of the

FutureWarning: `torch.cuda.amp.autocast(args...)` is deprecated. Please use `torch.amp.autocast('cuda', args...)` instead.
  with torch.cuda.amp.autocast(amp):

warning as mentioned in #13226.

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Update to use latest CUDA AMP (Automatic Mixed Precision) API across various files for better compatibility and performance.

📊 Key Changes

• Replaced torch.cuda.amp.autocast with torch.amp.autocast("cuda") in multiple files.
• Replaced torch.cuda.amp.GradScaler with torch.amp.GradScaler("cuda").

🎯 Purpose & Impact

• Improved Compatibility: Ensures that the code remains compatible with the latest PyTorch changes, reducing the risk of future issues.
• Performance: Leverages CUDA's improved automatic mixed precision to potentially enhance computational efficiency.
• Maintenance: Simplifies code adjustments related to AMP, making future updates easier to manage.

[github-actions]

All Contributors have signed the CLA. ✅
_{Posted by the CLA Assistant Lite bot.}

[github-actions]

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[jacobdbrown4]

I have read the CLA Document and I sign the CLA

[jacobdbrown4]

recheck

[glenn-jocher]

@jacobdbrown4 thank you for your comment! To ensure we address your issue effectively, could you please verify that you are using the latest versions of YOLOv5 and all related dependencies? This helps us confirm whether the problem persists with the most recent updates.

If the issue is still reproducible, please provide additional details such as error messages, steps to reproduce, and any relevant code snippets. This information will help us diagnose and resolve the issue more efficiently.

Looking forward to your response! 😊

[ijnrghjkdsmigywneig203]

This pull request needs to be merged, inference times are slower due to this error constantly popping up with the newest versions of pytorch.

[ijnrghjkdsmigywneig203]

@glenn-jocher

[glenn-jocher]

Thank you for your input. Please ensure you're using the latest YOLOv5 version to see if the issue persists. If the problem continues, provide additional details so we can assist further.