public async Task StartAsync_TaskHubStarts()
{
// arrange
Mock <IOrchestrationService> orchestrationMock = GetOrchestrationService();
var taskHubWorker = new TaskHubWorker(orchestrationMock.Object);
var service = new TaskHubBackgroundService(taskHubWorker, s_logger, s_options);
// act
await service.StartAsync(CancellationToken.None);
// assert
orchestrationMock.Verify(x => x.StartAsync(), Times.Once);
}