build(deps): bump express from 4.21.1 to 4.21.2

Bumps [express](https://github.com/expressjs/express) from 4.21.1 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@4.21.1...4.21.2)

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

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

Author: dependabot[bot]

packages/backend/package.json

@@ -101,7 +101,7 @@
   },
   "dependencies": {
     "@huggingface/gguf": "^0.1.12",
-    "express": "^4.21.1",
+    "express": "^4.21.2",
     "express-openapi-validator": "^5.3.9",
     "isomorphic-git": "^1.27.2",
     "js-yaml": "^4.1.0",