Remove usage of pathlib.Path.unlink(missing_ok=...)

[ymerkli]

Argument missing_ok in pathlib.Path.unlink() has only been introduced since Python 3.8, leading to errors when using Python 3.7.

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Improved file existence checks before deletion in various utility functions.

📊 Key Changes

• Modified autosplit function to explicitly check for file existence before attempting to delete auto-generated .txt files.
• Updated safe_download function to verify file presence before deletion to prevent possible file-not-found errors.
• Changed gdrive_download function to incorporate file presence verification ahead of file and cookie deletions.

🎯 Purpose & Impact

• The updates prevent potential errors that could arise when attempting to delete files that do not exist.
• Users will experience smoother operation without encountering exceptions related to file deletion, especially in environments that may not support the missing_ok parameter.
• Overall reliability of the download and autosplit processes within the repository is enhanced, leading to more robust data preparation and file handling operations.

[github-actions]

👋 Hello @ymerkli, thank you for submitting a YOLOv5 🚀 PR! To allow your work to be integrated as seamlessly as possible, we advise you to:

• ✅ Verify your PR is up-to-date with ultralytics/yolov5 master branch. If your PR is behind you can update your code by clicking the 'Update branch' button or by running git pull and git merge master locally.
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• ✅ Reduce changes to the absolute minimum required for your bug fix or feature addition. "It is not daily increase but daily decrease, hack away the unessential. The closer to the source, the less wastage there is." — Bruce Lee

[glenn-jocher]

@ymerkli good catch! PR is merged. Thank you for your contributions to YOLOv5 🚀 and Vision AI ⭐