Unhandled Exception: Bad state: No element

I tried multiple time to just test the pure example code from this repo but always ended with error!
basically i download the example code and add the exp package to it like that :
```
dependencies:
flutter:
sdk: flutter
responsive_builder: ^0.7.0
stacked: ^3.4.0
stacked_services: ^1.1.0

expression_ui:
path: expression-ui
```
and after run/restart issue (tested on emulator and real device) :

```
E/flutter (23338): [ERROR:flutter/runtime/dart_vm_initializer.cc(41)] Unhandled Exception: Bad state: No element
E/flutter (23338): #0 Iterable.first (dart:core/iterable.dart:643:7)
E/flutter (23338): #1 BaseExpressionView.onRiveFileInitialized (package:expression_ui/src/expression_widgets/base_expression_view.dart:117:14)
E/flutter (23338): #2 BaseExpressionView.build. (package:expression_ui/src/expression_widgets/base_expression_view.dart:65:29)
E/flutter (23338): #3 RiveAnimationState._init (package:rive/src/widgets/rive_animation.dart:323:20)
E/flutter (23338): #4 RiveAnimationState._configure (package:rive/src/widgets/rive_animation.dart:212:5)
E/flutter (23338):
E/flutter (23338):
```

i will try later to create a brand new stacked app with custom rive artboard and attach the result