chore: linkcheck failure

[github-actions]

Summary

Status	Count
🔍 Total	254
✅ Successful	242
⏳ Timeouts	2
🔀 Redirected	0
👻 Excluded	9
❓ Unknown	0
🚫 Errors	0

Errors per input

Errors in docs/src/reference/about.rst

• [TIMEOUT] https://allcontributors.org/docs/en/emoji-key | Timeout
• [TIMEOUT] https://allcontributors.org/docs/en/bot/usage#all-contributors-add | Timeout
  Full Github Actions output

[bjlittle]

Genuine service denial over on https://allcontributors.org/ atm