Fix anchor incorrectly initialized

[YellowAndGreen]

Using --noautoanchor and --evolve simultaneously leads to anchor incorrectly initialized. --noautoanchor denotes anchors don't need to evolve, thus removing anchors from hyp will fix it.

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Improved YOLOv5 model customization with auto-anchor disable option.

📊 Key Changes

• Added support to disable automatic anchor adjustment during training when specified by a new command-line option.

🎯 Purpose & Impact

• Purpose: Allows users more control over anchor settings during training by introducing the option to turn off the automatic adjustment of anchors, a key part of the YOLOv5 detection algorithm.
• Impact: Users who are experienced with the YOLO architecture or those wanting to experiment with fixed anchor sizes can potentially achieve better performance on custom datasets. This change enhances the flexibility of the model training process.

[github-actions]

👋 Hello @YellowAndGreen, 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 upstream/master. If your PR is behind upstream/master an automatic GitHub Actions merge may be attempted by writing /rebase in a new comment, or by running the following code, replacing 'feature' with the name of your local branch:

git remote add upstream https://github.com/ultralytics/yolov5.git
git fetch upstream
# git checkout feature  # <--- replace 'feature' with local branch name
git merge upstream/master
git push -u origin -f

• ✅ Verify all Continuous Integration (CI) checks are passing.
• ✅ 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]

@YellowAndGreen PR is merged. Thank you for your contributions to YOLOv5 🚀 and Vision AI ⭐