Update downloads.py current release

[Powercube7]

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Update to default download version in utils/downloads.py.

📊 Key Changes

• Updated the default tag in the attempt_download function to 'v6.1'.

🎯 Purpose & Impact

• This change ensures users retrieve the latest stable release when an automatic download is attempted.
• It keeps users up to date with the newest features and bug fixes, enhancing overall user experience.

[github-actions]

👋 Hello @Powercube7, 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]

@Powercube7 good catch! I don't know how I missed this.

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