remove legacy reference

@@ -8,6 +8,5 @@ export 'src/rx_flutter/rx_ticket_provider_mixin.dart';
 export 'src/simple/get_responsive.dart';
 export 'src/simple/get_responsive.dart';
 export 'src/simple/get_state.dart';
 export 'src/simple/get_state.dart';
 export 'src/simple/get_view.dart';
 export 'src/simple/get_view.dart';
-export 'src/simple/immutable_state.dart';
 export 'src/simple/mixin_state.dart';
 export 'src/simple/mixin_state.dart';
 export 'src/simple/simple_builder.dart';
 export 'src/simple/simple_builder.dart';