GH.UI.UnitTests depends on GH.VisualStudio.UI

GitHub.UI.UnitTests has an implicit dependency on
GitHub.VisualStudio.UI via:
pack://application:,,,/GitHub.VisualStudio.UI;component/SharedDictionary.xaml

Author: jcansdale

test/GitHub.UI.UnitTests/GitHub.UI.UnitTests.csproj

@@ -77,6 +77,10 @@
     </None>
   </ItemGroup>
   <ItemGroup>
+    <ProjectReference Include="..\..\src\GitHub.VisualStudio.UI\GitHub.VisualStudio.UI.csproj">
+      <Project>{d1dfbb0c-b570-4302-8f1e-2e3a19c41961}</Project>
+      <Name>GitHub.VisualStudio.UI</Name>
+    </ProjectReference>
     <ProjectReference Include="..\..\submodules\octokit.net\Octokit\Octokit.csproj">
       <Project>{08dd4305-7787-4823-a53f-4d0f725a07f3}</Project>
       <Name>Octokit</Name>