fix: backend/package.json & backend/package-lock.json to reduce vulne…

…rabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-COOKIE-8163060

backend/package.json

@@ -14,16 +14,16 @@
     "axios": "^1.7.2",
     "bcryptjs": "^2.4.3",
     "body-parser": "^1.20.2",
-    "cookie-parser": "^1.4.6",
+    "cookie-parser": "^1.4.7",
     "cors": "^2.8.5",
     "discord.js": "^14.12.1",
     "dotenv": "^16.4.5",
     "esm": "^3.2.25",
-    "express": "^4.19.2",
+    "express": "^4.21.1",
     "express-jwt": "^8.4.1",
     "express-openid-connect": "^2.17.1",
     "express-rate-limit": "^7.4.0",
-    "express-session": "^1.18.0",
+    "express-session": "^1.18.1",
     "fs": "^0.0.1-security",
     "helmet": "^7.1.0",
     "jsonwebtoken": "^9.0.2",