[master] Update dependencies from dotnet/arcade Microsoft/vstest (#790)

[master] Update dependencies from dotnet/arcade Microsoft/vstest (#790)

* Update dependencies from https://github.com/dotnet/arcade build 20191211.6

- Microsoft.DotNet.XUnitExtensions - 5.0.0-beta.19611.6
- Microsoft.DotNet.XUnitConsoleRunner - 2.5.1-beta.19611.6
- Microsoft.DotNet.VersionTools.Tasks - 5.0.0-beta.19611.6
- Microsoft.DotNet.ApiCompat - 5.0.0-beta.19611.6
- Microsoft.DotNet.Arcade.Sdk - 5.0.0-beta.19611.6
- Microsoft.DotNet.Build.Tasks.Configuration - 5.0.0-beta.19611.6
- Microsoft.DotNet.Build.Tasks.Feed - 5.0.0-beta.19611.6
- Microsoft.DotNet.Build.Tasks.Packaging - 5.0.0-beta.19611.6
- Microsoft.DotNet.Build.Tasks.SharedFramework.Sdk - 5.0.0-beta.19611.6
- Microsoft.DotNet.CodeAnalysis - 5.0.0-beta.19611.6
- Microsoft.DotNet.GenAPI - 5.0.0-beta.19611.6
- Microsoft.DotNet.GenFacades - 5.0.0-beta.19611.6
- Microsoft.DotNet.Helix.Sdk - 5.0.0-beta.19611.6
- Microsoft.DotNet.RemoteExecutor - 5.0.0-beta.19611.6

* Update dependencies from https://github.com/microsoft/vstest build 20191211-02

- Microsoft.NET.Test.Sdk - 16.5.0-preview-20191211-02