Revert "Update torch_utils.py import LOGGER"

[glenn-jocher]

Reverts #5483 to attempt CI failure fix.

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Enhanced model export compatibility and internal logging refinement.

📊 Key Changes

• Added Keras version specification (keras==2.6.0) to the model export dependencies.
• Corrected the new line issue at the end of tutorial.ipynb.
• Moved the LOGGER definition directly into utils/torch_utils.py.

🎯 Purpose & Impact

• Keras version pinning ensures consistency and compatibility when exporting models, preventing issues with future Keras updates.🔒
• New line fix in the Jupyter notebook doesn't impact functionality but adheres to file format best practices. 📝
• LOGGER relocation makes logging within torch_utils.py more self-contained and could improve module independence and readability. 🧾

Overall, these changes are poised to enhance the developer experience and the stability of model export features for end users.