chore(deps): bump engine.io from 5.2.1 to 6.4.2 in /ci

Bumps [engine.io](https://github.com/socketio/engine.io) from 5.2.1 to 6.4.2.
- [Release notes](https://github.com/socketio/engine.io/releases)
- [Changelog](https://github.com/socketio/engine.io/blob/main/CHANGELOG.md)
- [Commits](socketio/engine.io@5.2.1...6.4.2)

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

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

ci/package.json

@@ -5,7 +5,7 @@
   "author": "Bastian Kersting",
   "license": "MIT",
   "dependencies": {
-    "engine.io": "5.2.1",
+    "engine.io": "6.4.2",
     "socket.io": "4.0.0"
   }
 }