Support Test Explorer `Trait` groupping

[xperiandri]

Path till the test name should be reported as Trait to Visual Studio

[Alxandr]

Feel free to create a PR :)

[Alxandr]

@xperiandri I looked at this, but TestCase has a trait collection. And I don't have Visual Studio to test in, nor do I find any good documentation for this. Can you please describe exactly the feature you're requesting?