fix: expose user_role model

Author: fulleni

lib/src/models/models.dart

@@ -7,3 +7,4 @@ export 'response_metadata.dart';
 export 'source.dart';
 export 'success_api_response.dart';
 export 'user.dart';
+export 'user_role.dart';

test/src/models/auth_success_response_test.dart

@@ -1,5 +1,4 @@
 import 'package:ht_shared/ht_shared.dart';
-import 'package:ht_shared/src/models/user_role.dart';
 import 'package:test/test.dart';
 
 void main() {