move to new System.Threading.Lock type for better performance

Emby.Server.Implementations/ScheduledTasks/ScheduledTaskWorker.cs

@@ -27,7 +27,7 @@ namespace Emby.Server.Implementations.ScheduledTasks
         private readonly IApplicationPaths _applicationPaths;
         private readonly ILogger _logger;
         private readonly ITaskManager _taskManager;
-        private readonly object _lastExecutionResultSyncLock = new();
+        private readonly Lock _lastExecutionResultSyncLock = new();
         private bool _readFromFile;
         private TaskResult _lastExecutionResult;
         private Task _currentTask;