“等待”放在哪里?

这里有一个1方法的类,

public class ApiService
{
    public async Task StartAsync()
    {
        await _webHost.StartAsync();
    }
}

现在尝试像下面这样调用上面的类/方法,

public static async Task Main(string[] args)
    {

        HostFactory.Run(
        configuration =>
        {
            configuration.Service<ApiService>(
                service =>
                {
                    service.ConstructUsing(x => new ApiService());
                    service.WhenStarted(x => x.StartAsync());
                });

            configuration.RunAsLocalSystem();
        });
    }

如果我把 await 像这样,它给出了错误,在哪里放置异步/等待?

service.WhenStarted(x => await x.StartAsync());