Bump express from 4.19.2 to 4.21.0

Bumps [express](https://github.com/expressjs/express) from 4.19.2 to 4.21.0.
- [Release notes](https://github.com/expressjs/express/releases)
- [Changelog](https://github.com/expressjs/express/blob/4.21.0/History.md)
- [Commits](https://github.com/expressjs/express/compare/4.19.2...4.21.0)

---
updated-dependencies:
- dependency-name: express
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

package.json

@@ -12,7 +12,7 @@
   },
   "dependencies": {
     "cors": "^2.8.5",
-    "express": "^4.19.2",
+    "express": "^4.21.0",
     "socket.io": "^4.7.5",
     "ssh2": "^1.15.0"
   },