Bump ws and pa11y in /docs/tools/.sphinx (#504)

Bumps [ws](https://github.com/websockets/ws) to 8.17.1 and updates ancestor dependency [pa11y](https://github.com/pa11y/pa11y). These dependencies need to be updated together.


Updates `ws` from 8.13.0 to 8.17.1
- [Release notes](https://github.com/websockets/ws/releases)
- [Commits](websockets/ws@8.13.0...8.17.1)

Updates `pa11y` from 7.0.0 to 8.0.0
- [Release notes](https://github.com/pa11y/pa11y/releases)
- [Changelog](https://github.com/pa11y/pa11y/blob/main/CHANGELOG.md)
- [Commits](pa11y/pa11y@7.0.0...8.0.0)

---
updated-dependencies:
- dependency-name: ws
  dependency-type: indirect
- dependency-name: pa11y
  dependency-type: direct:production
...

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