fix models

packages/stream_chat/lib/src/models/read.g.dart

@@ -6,12 +6,10 @@ part of 'read.dart';
 // JsonSerializableGenerator
 // **************************************************************************
 
-Read _$ReadFromJson(Map json) {
+Read _$ReadFromJson(Map<String, dynamic> json) {
   return Read(
     lastRead: DateTime.parse(json['last_read'] as String),
-    user: User.fromJson((json['user'] as Map?)?.map(
-      (k, e) => MapEntry(k as String, e),
-    )),
+    user: User.fromJson(json['user'] as Map<String, dynamic>?),
     unreadMessages: json['unread_messages'] as int,
   );
 }