Bump ws and engine.io-client in /src/ifctester/webapp

Bumps [ws](https://github.com/websockets/ws) and [engine.io-client](https://github.com/socketio/socket.io). These dependencies needed to be updated together.

Updates `ws` from 8.17.1 to 8.21.0
- [Release notes](https://github.com/websockets/ws/releases)
- [Commits](https://github.com/websockets/ws/compare/8.17.1...8.21.0)

Updates `engine.io-client` from 6.6.3 to 6.6.6
- [Release notes](https://github.com/socketio/socket.io/releases)
- [Changelog](https://github.com/socketio/socket.io/blob/main/CHANGELOG.md)
- [Commits](https://github.com/socketio/socket.io/compare/engine.io-client@6.6.3...engine.io-client@6.6.6)

---
updated-dependencies:
- dependency-name: ws
  dependency-version: 8.21.0
  dependency-type: indirect
- dependency-name: engine.io-client
  dependency-version: 6.6.6
  dependency-type: indirect
...

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