remove unused variable

Author: lohanidamodar

templates/flutter/lib/src/realtime_mixin.dart.twig

@@ -21,7 +21,6 @@ mixin RealtimeMixin {
   late WebSocketFactory getWebSocket;
   GetFallbackCookie? getFallbackCookie;
   int? get closeCode => _websok?.closeCode;
-  int _subscriptionsCounter = 0;
   Map<int, RealtimeSubscription> _subscriptions = {};
   bool _notifyDone = true;
   StreamSubscription? _websocketSubscription;