Remove p-limit dependency

It was introduced as part of
#6069
to support a cron job that no longer exists.

Author: Vinnl

package-lock.json

@@ -103,7 +103,6 @@
     "next": "15.5.4",
     "next-auth": "^4.24.13",
     "nodemailer": "^7.0.10",
-    "p-limit": "^7.1.1",
     "pg": "^8.16.3",
     "raw-loader": "^4.0.2",
     "react": "19.1.1",