fixup! Migrate tests to Xunit.Net 2.0

Author: nulltoken

LibGit2Sharp.Tests/LibGit2Sharp.Tests.csproj

@@ -47,7 +47,6 @@
     </Reference>
     <Reference Include="xunit.assert">
       <HintPath>..\packages\xunit.assert.2.0.0-beta5-build2785\lib\portable-net45+aspnetcore50+win+wpa81+wp80+monoandroid+monotouch10\xunit.assert.dll</HintPath>
-      <Private>True</Private>
     </Reference>
     <Reference Include="xunit.core">
       <HintPath>..\packages\xunit.core.2.0.0-beta5-build2785\lib\portable-net45+aspnetcore50+win+wpa81+wp80+monotouch+monoandroid\xunit.core.dll</HintPath>