Bump engine.io from 6.2.0 to 6.2.1 in /user-registration-app

Bumps [engine.io](https://github.com/socketio/engine.io) from 6.2.0 to 6.2.1.
- [Release notes](https://github.com/socketio/engine.io/releases)
- [Changelog](https://github.com/socketio/engine.io/blob/main/CHANGELOG.md)
- [Commits](socketio/engine.io@6.2.0...6.2.1)

---
updated-dependencies:
- dependency-name: engine.io
  dependency-type: indirect
...

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