Add explicit Django AppConfig to set default_auto_field (#769)

Author: diesieben07

push_notifications/apps.py

@@ -0,0 +1,6 @@
+from django.apps import AppConfig
+
+
+class PushNotificationsConfig(AppConfig):
+	name = "push_notifications"
+	default_auto_field = "django.db.models.AutoField"