Make GitHubPane await initialization of IGitHubPaneViewModel

GitHubPackage shouldn't be concerned about this.

Author: jcansdale

src/GitHub.VisualStudio/GitHubPackage.cs

@@ -149,9 +149,7 @@ public async Task<IGitHubPaneViewModel> ShowGitHubPane()
             }
 
             var gitHubPane = (GitHubPane)pane;
-            var viewModel = await gitHubPane.GetViewModelAsync();
-            await viewModel.InitializeAsync(pane);
-            return viewModel;
+            return await gitHubPane.GetViewModelAsync();
         }
 
         static ToolWindowPane ShowToolWindow(Guid windowGuid)

src/GitHub.VisualStudio/UI/GitHubPane.cs

@@ -101,7 +101,7 @@ async Task InitializeAsync()
 
             var factory = provider.GetService<IViewViewModelFactory>();
             var viewModel = provider.ExportProvider.GetExportedValue<IGitHubPaneViewModel>();
-            viewModel.InitializeAsync(this).Catch(ShowError).Forget();
+            await viewModel.InitializeAsync(this);
 
             View = factory.CreateView<IGitHubPaneViewModel>();
             View.DataContext = viewModel;