Describe the style change

The blank lines between a function's definition and its docstring currently get removed by Black. However, it does not do the same thing for classes.

Current Black changes

def f():

    """The line above gets removed."""
    return 0

becomes

def f():
    """The line above gets removed."""
    return 0

but

class C:

    """The line above stays."""

is not modified by Black.

Desired style

I would have expected that code to get reformatted as:

class C:
    """The line above stays."""