updated project style guidelines

lib/api/marianumcloud/talk/sendMessage/sendMessage.dart

@@ -10,9 +10,7 @@ class SendMessage extends TalkApi {
   SendMessage(this.chatToken, SendMessageParams params) : super('v1/chat/$chatToken', params);
 
   @override
-  assemble(String raw) {
-    return null;
-  }
+  assemble(String raw) => null;
 
   @override
   Future<Response>? request(Uri uri, ApiParams? body, Map<String, String>? headers) {
@@ -22,4 +20,4 @@ class SendMessage extends TalkApi {
     return null;
   }
   
-}
+}

lib/api/marianumcloud/talk/sendMessage/sendMessageParams.dart

@@ -13,4 +13,4 @@ class SendMessageParams extends ApiParams {
 
   factory SendMessageParams.fromJson(Map<String, dynamic> json) => _$SendMessageParamsFromJson(json);
   Map<String, dynamic> toJson() => _$SendMessageParamsToJson(this);
-}
+}

lib/api/marianumcloud/talk/sendMessage/sendMessageResponse.dart

@@ -2,4 +2,4 @@ import '../../../apiResponse.dart';
 
 class SendMessageResponse extends ApiResponse {
 
-}
+}