switch back to jsonmessageformatter

Author: taooceros

Flow.Launcher.Core/Plugin/JsonRPCPluginV2.cs

@@ -91,7 +91,7 @@ async Task ReadErrorAsync()
 
         private void SetupJsonRPC()
         {
-            var formatter = new SystemTextJsonFormatter();
+            var formatter = new JsonMessageFormatter();
             var handler = new NewLineDelimitedMessageHandler(ClientPipe,
                 formatter);