chore(deps): bump soupsieve from 2.8.4 to 2.9 in /docs (#6181)

Bumps [soupsieve](https://github.com/facelessuser/soupsieve) from 2.8.4 to 2.9.
- [Release notes](https://github.com/facelessuser/soupsieve/releases)
- [Commits](https://github.com/facelessuser/soupsieve/compare/2.8.4...2.9)

---
updated-dependencies:
- dependency-name: soupsieve
  dependency-version: '2.9'
  dependency-type: indirect
...

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