chore(deps): update dependency @types/multer to v2

Author: renovate[bot]

packages/backend/package.json

@@ -126,7 +126,7 @@
     "@types/jest": "^29.5.14",
     "@types/lodash.isequal": "^4.5.8",
     "@types/lodash.set": "^4.3.9",
-    "@types/multer": "^1.4.13",
+    "@types/multer": "^2.0.0",
     "@types/node": "^20.19.2",
     "@types/node-pdftk": "^2.1.9",
     "@types/nodemailer": "^6.4.17",