Clean up unused usings

Signed-off-by: Victor Chang <vicchang@nvidia.com>

Author: mocsharp

src/InformaticsGateway/Program.cs

@@ -29,8 +29,6 @@
 using Monai.Deploy.InformaticsGateway.Common;
 using Monai.Deploy.InformaticsGateway.Configuration;
 using Monai.Deploy.InformaticsGateway.Database;
-using Monai.Deploy.InformaticsGateway.Database.Api.Repositories;
-using Monai.Deploy.InformaticsGateway.Database.EntityFramework.Repositories;
 using Monai.Deploy.InformaticsGateway.Repositories;
 using Monai.Deploy.InformaticsGateway.Services.Common;
 using Monai.Deploy.InformaticsGateway.Services.Connectors;

src/InformaticsGateway/Services/Storage/ObjectUploadQueue.cs

@@ -16,7 +16,6 @@
 
 using System;
 using System.Collections.Concurrent;
-using System.Collections.Generic;
 using System.Diagnostics;
 using System.Threading;
 using System.Threading.Tasks;