[feature request] Codelens for TestFixture

[Thaina]

Please add ability to run test and debug test on TestFixture with nunit

[akshita31]

@Thaina We already have a codelens showing up for a Nunit project. Also, with the change in #1961 , we added the capability to run and debug all the tests in the class.

This change is available in the latest beta release, if you're interested in giving it a spin. Follow these instructions to install a beta release of C# for VS Code.

[DustinCampbell]

This is a dupe of #420, which as @akshita31 mentioned, is already fixed for the next release. Feel free to take a beta release for a spin if you're interested.