Only displaying the fork functionality for github.com repos

Author: StanleyGoldman

src/GitHub.TeamFoundation.14/Home/ForkNavigationItem.cs

@@ -97,7 +97,7 @@ public override async void Invalidate()
             {
                 IsVisible = false;
 
-                if ((packageSettings?.ForkButton ?? false) && await IsAGitHubRepo())
+                if ((packageSettings?.ForkButton ?? false) && await IsAGitHubDotComRepo())
                 {
                     var connection = await ConnectionManager.GetConnection(ActiveRepo);
                     IsVisible = connection?.IsLoggedIn ?? false;

src/GitHub.VisualStudio.UI/Base/TeamExplorerItemBase.cs

@@ -141,6 +141,12 @@ protected async Task<bool> IsAGitHubRepo()
             return origin == RepositoryOrigin.DotCom || origin == RepositoryOrigin.Enterprise;
         }
 
+        protected async Task<bool> IsAGitHubDotComRepo()
+        {
+            var origin = await GetRepositoryOrigin();
+            return origin == RepositoryOrigin.DotCom;
+        }
+
         protected async Task<bool> IsUserAuthenticated()
         {
             if (SimpleApiClient == null)