Removing unused import

Author: StanleyGoldman

src/GitHub.VisualStudio/GitHubPackage.cs

@@ -20,7 +20,6 @@
 using Microsoft.VisualStudio.Shell;
 using Microsoft.VisualStudio.Shell.Interop;
 using Octokit;
-using Rothko;
 using Serilog;
 using Task = System.Threading.Tasks.Task;