chore(deps): bump express from 4.19.2 to 4.21.2

Bumps [express](https://github.com/expressjs/express) from 4.19.2 to 4.21.2.
- [Release notes](https://github.com/expressjs/express/releases)
- [Changelog](https://github.com/expressjs/express/blob/4.21.2/History.md)
- [Commits](expressjs/express@4.19.2...4.21.2)

---
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

@@ -18,7 +18,7 @@
     "@types/node": "^20.14.2",
     "cors": "^2.8.5",
     "dotenv": "^16.4.5",
-    "express": "^4.19.2",
+    "express": "^4.21.2",
     "npm-check-updates": "^16.14.20",
     "openai": "^4.71.1",
     "react": "^18.3.1",