fix：跨子系统映射赋值问题

src/SJZY.Track.Application/EventHandlers/TrackUpsertEventHandler.cs

@@ -80,7 +80,7 @@ public class TrackUpsertEventHandler : ITransientDependency, ICapSubscribe
                         return;
                     }
 
-                    @event.TrackCode = mapCode;
+                    nextEvent.TrackCode = mapCode;
                 }
 
                 await _capPublisher.PublishAsync(GlobalConst.TrackUpsertSubscribe, nextEvent);