fixed tests

packages/stream_chat/lib/src/core/models/event.dart

@@ -93,6 +93,7 @@ class Event {
   final bool isLocal;
 
   /// This is true if the message has been hard deleted
+  @JsonKey(includeIfNull: false)
   final bool? hardDelete;
 
   /// Map of custom channel extraData

packages/stream_chat/lib/src/core/models/event.g.dart

@@ -42,7 +42,8 @@ Event _$EventFromJson(Map<String, dynamic> json) => Event(
       isLocal: json['is_local'] as bool? ?? false,
     );
 
-Map<String, dynamic> _$EventToJson(Event instance) => <String, dynamic>{
+Map<String, dynamic> _$EventToJson(Event instance) {
+  final val = <String, dynamic>{
     'type': instance.type,
     'cid': instance.cid,
     'channel_id': instance.channelId,
@@ -60,10 +61,19 @@ Map<String, dynamic> _$EventToJson(Event instance) => <String, dynamic>{
     'online': instance.online,
     'parent_id': instance.parentId,
     'is_local': instance.isLocal,
-      'hard_delete': instance.hardDelete,
-      'extra_data': instance.extraData,
   };
 
+  void writeNotNull(String key, dynamic value) {
+    if (value != null) {
+      val[key] = value;
+    }
+  }
+
+  writeNotNull('hard_delete', instance.hardDelete);
+  val['extra_data'] = instance.extraData;
+  return val;
+}
+
 EventChannel _$EventChannelFromJson(Map<String, dynamic> json) => EventChannel(
       members: (json['members'] as List<dynamic>?)
           ?.map((e) => Member.fromJson(e as Map<String, dynamic>))