chore(deps): update express requirement from ^4.19.2 to ^4.21.1

Updates the requirements on [express](https://github.com/expressjs/express) to permit the latest version.
- [Release notes](https://github.com/expressjs/express/releases)
- [Changelog](https://github.com/expressjs/express/blob/4.21.1/History.md)
- [Commits](expressjs/express@4.19.2...4.21.1)

---
updated-dependencies:
- dependency-name: express
  dependency-type: direct:production
...

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

package.json

@@ -26,7 +26,7 @@
     "connect-flash": "^0.1.1",
     "cookie-parser": "^1.4.7",
     "cookie-signature": "^1.2.1",
-    "express": "^4.19.2",
+    "express": "^4.21.1",
     "express-session": "^1.18.0",
     "iobroker.simple-api": "^2.8.0",
     "iobroker.ws": "2.6.2",