docs: remove broken kind/question label reference

[CyberRaccoonTeam]

Fixes #10765

Problem

The documentation referenced a non-existent kind/question label that results in a 404 error.

Solution

• Removed the broken kind/question label reference from the "Documentation contributions" section
• Removed the corresponding link reference from the bottom of the file

Testing

• Verified that the kind/question label does not exist in the Poetry repository
• Confirmed that the GitHub Discussions link (which was also mentioned) is still valid
• All pre-commit hooks passed

[sourcery-ai]

Hey - I've reviewed your changes and they look great!

---

Sourcery is free for open source - if you like our reviews please consider sharing them ✨

• X
• Mastodon
• LinkedIn
• Facebook

_{Help me be more useful! Please click 👍 or 👎 on each comment and I'll use the feedback to improve your reviews.}