Small fixes to docstrings

[zhiqwang]

Hi @glenn-jocher

This PR does the following three things:

• Fix markdown formatting
• Use em dash to quote https://en.wikipedia.org/wiki/Dash#Types_of_dash
• Maybe we should up-to-date with the upstream/master?

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Updated contributor guidance and automated welcome message in the YOLOv5 repository.

📊 Key Changes

• Modified the GitHub greetings workflow to change the indentation of bash commands.
• Updated the CONTRIBUTING.md documentation, adjusting the indentation of a bash command snippet and removing a quote from Bruce Lee.

🎯 Purpose & Impact

• Ensure consistency and readability in documentation and automated messages, which benefits contributors when setting up their local environment for contributions.
• The removal of the quote streamlines the contributing guidelines, focusing the content on technical instructions only. This may help in reducing distractions and making the document more focused and concise for contributors.

[glenn-jocher]

@zhiqwang oh thanks for pointing out the discrepancy! Now that I look at it maybe it makes more sense to rename upstream to origin. In PyCharm it shows the remote github branches as origin. What do you think?

[zhiqwang]

Hi @glenn-jocher

Now that I look at it maybe it makes more sense to rename upstream to origin. In PyCharm it shows the remote github branches as origin. What do you think?

Seems to be origin only for you, because you have permission to work directly on https://github.com/ultralytics/yolov5, but for third party developers it is upstream, like for me, the origin I am currently working on is https://github.com/zhiqwang/yolov5 .

[glenn-jocher]

@zhiqwang oh got it! origin is your fork, upstream is the repo that was forked. Yes you are right.

[glenn-jocher]

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