Remove unused field gitHubContextService

Remove gitHubContextService from OpenFromUrlCommand.

Author: jcansdale

src/GitHub.VisualStudio/Commands/OpenFromUrlCommand.cs

@@ -11,7 +11,6 @@ namespace GitHub.VisualStudio.Commands
     public class OpenFromUrlCommand : VsCommand<string>, IOpenFromUrlCommand
     {
         readonly Lazy<IDialogService> dialogService;
-        readonly Lazy<IGitHubContextService> gitHubContextService;
         readonly Lazy<IRepositoryCloneService> repositoryCloneService;
 
         /// <summary>
@@ -27,12 +26,10 @@ public class OpenFromUrlCommand : VsCommand<string>, IOpenFromUrlCommand
         [ImportingConstructor]
         public OpenFromUrlCommand(
             Lazy<IDialogService> dialogService,
-            Lazy<IGitHubContextService> gitHubContextService,
             Lazy<IRepositoryCloneService> repositoryCloneService) :
             base(CommandSet, CommandId)
         {
             this.dialogService = dialogService;
-            this.gitHubContextService = gitHubContextService;
             this.repositoryCloneService = repositoryCloneService;
 
             // See https://code.msdn.microsoft.com/windowsdesktop/AllowParams-2005-9442298f