convert title cased class names to sentence

[satyanash]

If I have a test nested inside a class:

class TestFoobar:
  class TestWhenFooIsBar:
    def test_it_should_do_something():
      assert 1 == 1

It should convert the class name to a sentence When Foo Is Bar as follows :

Foobar:
  When Foo Is Bar:
    ✓ it should do something:

Right now, it simply outs it as as it is: WhenFooIsBar. A temporary workaround could be #44, but even that requires double work to add docstrings when your class names may already be descriptive enough.

[0x64746b]

Fwiw, splitting non-nested, top-level class names once worked but apparently broke with https://github.com/pchomik/pytest-spec/pull/18/files#diff-70bfff549b1975eda90e09b38b990f495ad9d24c3899ced8e49f3cf418a43634L72 🤷