public void TaskCountingPeriodTasksTest()
        {
            using (var taskScheduler2 = new TaskScheduler(Mock.Of <IShamanLogger>()))
            {
                _taskScheduler.ScheduleOnInterval(() => { Thread.Sleep(100); }, 10, 10);
                _taskScheduler.ScheduleOnInterval(() => { Thread.Sleep(100); }, 10, 10);
                _taskScheduler.ScheduleOnInterval(() => { Thread.Sleep(100); }, 10, 10);
                _taskScheduler.ScheduleOnInterval(() => { Thread.Sleep(100); }, 10, 10);

                PendingTask.GetActivePeriodicTimersCount().Should().Be(4 + TaskSchedulerInternalPeriodicTimersCount);
                PendingTask.GetActivePeriodicSlTimersCount().Should().Be(0);

                taskScheduler2.ScheduleOnInterval(() => { Thread.Sleep(100); }, 10, 10);

                PendingTask.GetActivePeriodicTimersCount().Should().Be(5 + TaskSchedulerInternalPeriodicTimersCount);
                PendingTask.GetActivePeriodicSlTimersCount().Should().Be(0);
            }
        }