Bump socket.io from 2.4.0 to 2.5.0 in /packages/web-component-tester

Bumps [socket.io](https://github.com/socketio/socket.io) from 2.4.0 to 2.5.0.
- [Release notes](https://github.com/socketio/socket.io/releases)
- [Changelog](https://github.com/socketio/socket.io/blob/main/CHANGELOG.md)
- [Commits](socketio/socket.io@2.4.0...2.5.0)

---
updated-dependencies:
- dependency-name: socket.io
  dependency-type: direct:production
...

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