Update HangfireBackgroundWorkerManager.cs

framework/src/Volo.Abp.BackgroundWorkers.Hangfire/Volo/Abp/BackgroundWorkers/Hangfire/HangfireBackgroundWorkerManager.cs

@@ -1,10 +1,8 @@
 using System;
-using System.Linq.Expressions;
 using System.Reflection;
 using System.Threading;
 using System.Threading.Tasks;
 using Hangfire;
-using Hangfire.Common;
 using Microsoft.Extensions.DependencyInjection;
 using Volo.Abp.DependencyInjection;
 using Volo.Abp.DynamicProxy;