Bump socket.io and karma

Bumps [socket.io](https://github.com/socketio/socket.io) to 4.7.5 and updates ancestor dependency [karma](https://github.com/karma-runner/karma). These dependencies need to be updated together.


Updates `socket.io` from 2.1.1 to 4.7.5
- [Release notes](https://github.com/socketio/socket.io/releases)
- [Changelog](https://github.com/socketio/socket.io/blob/main/CHANGELOG.md)
- [Commits](socketio/socket.io@2.1.1...4.7.5)

Updates `karma` from 3.1.4 to 6.4.3
- [Release notes](https://github.com/karma-runner/karma/releases)
- [Changelog](https://github.com/karma-runner/karma/blob/master/CHANGELOG.md)
- [Commits](karma-runner/karma@v3.1.4...v6.4.3)

---
updated-dependencies:
- dependency-name: socket.io
  dependency-type: indirect
- dependency-name: karma
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <[email protected]>