build(deps): bump qs and express in /webapp/backend

Bumps [qs](https://github.com/ljharb/qs) to 6.15.2 and updates ancestor dependency [express](https://github.com/expressjs/express). These dependencies need to be updated together.


Updates `qs` from 6.14.2 to 6.15.2
- [Changelog](https://github.com/ljharb/qs/blob/main/CHANGELOG.md)
- [Commits](ljharb/qs@v6.14.2...v6.15.2)

Updates `express` from 4.22.1 to 4.22.2
- [Release notes](https://github.com/expressjs/express/releases)
- [Changelog](https://github.com/expressjs/express/blob/v4.22.2/History.md)
- [Commits](expressjs/express@v4.22.1...v4.22.2)

---
updated-dependencies:
- dependency-name: qs
  dependency-version: 6.15.2
  dependency-type: indirect
- dependency-name: express
  dependency-version: 4.22.2
  dependency-type: direct:production
...

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

Author: dependabot[bot]

webapp/backend/package-lock.json

@@ -11,7 +11,7 @@
   },
   "dependencies": {
     "cors": "^2.8.5",
-    "express": "^4.21.2",
+    "express": "^4.22.2",
     "express-rate-limit": "^7.5.0",
     "helmet": "^8.1.0"
   },