Update dependency @react-native-firebase/app to v20.4.0

Author: renovate[bot]

package.json

@@ -13,7 +13,7 @@
   },
   "dependencies": {
     "@react-native-community/datetimepicker": "8.2.0",
-    "@react-native-firebase/app": "20.1.0",
+    "@react-native-firebase/app": "20.4.0",
     "@react-native-firebase/messaging": "20.1.0",
     "@react-navigation/native": "6.1.17",
     "@react-navigation/native-stack": "6.10.0",