52116: Legacy FCM server key credential used to send notifications

Google will deprecate the legacy FCM API in June 2024: https://help.twilio.com/articles/20768292997147-Updating-Twilio-Push-for-FCM-HTTP-v1-API

Detected the use of a legacy FCM server key credential. This credential will stop working after Google deprecates the legacy FCM API in June 2024. Your action is required in order for FCM push notifications to continue to work after the legacy FCM API is deprecated.

Use a new FCMv1 credential before June 2024 to keep sending push notifications. See instructions linked in the description above.