Bump ws in /frontend

Bumps  and [ws](https://github.com/websockets/ws). These dependencies needed to be updated together.

Updates `ws` from 8.5.0 to 8.21.0
- [Release notes](https://github.com/websockets/ws/releases)
- [Commits](websockets/ws@8.5.0...8.21.0)

Updates `ws` from 6.2.2 to 6.2.4
- [Release notes](https://github.com/websockets/ws/releases)
- [Commits](websockets/ws@8.5.0...8.21.0)

---
updated-dependencies:
- dependency-name: ws
  dependency-version: 8.21.0
  dependency-type: indirect
- dependency-name: ws
  dependency-version: 6.2.4
  dependency-type: indirect
...

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Author: dependabot[bot]