Upgrading firebase-admin to 12.2.0 (#476)

Picks up firebase/firebase-admin-node#2553 which unlocks using application default credentials for local development.

Author: maxl0rd

js/plugins/firebase/package.json

@@ -40,7 +40,7 @@
   },
   "peerDependencies": {
     "@google-cloud/firestore": "^7.6.0",
-    "firebase-admin": "^12.1.0",
+    "firebase-admin": "^12.2.0",
     "firebase-functions": "^4.8.0 || ^5.0.0"
   },
   "devDependencies": {