Don't omit empty parentheses for hardcoded class docstrings

[laurensvalk]

Is your feature request related to a problem? Please describe.
It would be nice to show empty parentheses () for overloaded classes, such that all signatures look consistent. Right now (Sphinx 4.4.0), they look different:

Describe the solution you'd like
Show empty parentheses for overloaded class signatures:

class MyBool()
class MyBool(x: any)

Additional context
Originally reported here: pybricks/pybricks-api#85

Related issue:
#10280

[laurensvalk]

If we take the specific case where docstrings are manually overridden, then this could perhaps be considered as a bug.

Take this example:

class MyComplex:

    def __init__(self, *args):
        """MyComplex()
        MyComplex(string: str)
        MyComplex(a: Union[float, complex], b: Union[float, complex] = 0)

        The () are omitted on first case even though they are entered explicitly.
        """

This gets rendered as:

Workaround (and possible minor fix without too many breaking changes).

It does render it if you add a zero-size whitespace character.

This gives:

It looks like every other character gets rendered too except a normal space.

So perhaps this could be make to work by allowing a normal space here.

[laurensvalk]

I'm closing this as the proposed workaround works well enough.