[Feature Request] Add typing for signal for PyCharm

[trajano]

Is your feature request related to a problem? Please describe.

PyCharm complains on a no-arg signal

await handler.signal(PlaceholderWorkflow.terminate)

Describe the solution you'd like

Can this be added to WorkflowHandle in client.py

    @overload
    async def signal(
        self,
        signal: Callable[SelfType, None],
        *,
        rpc_metadata: Mapping[str, Union[str, bytes]] = {},
        rpc_timeout: Optional[timedelta] = None,
    ) -> None: ...

Additional context

PyRight works, just PyCharm isn't working as expected but having that line works in both PyRight and PyCharm

[tconley1428]

I actually wasn't able to reproduce this in my version of PyCharm. Potentially that's configuration or version dependent. Regardless, this overload doesn't actually expand the range of valid types, as Callable would fit the protocol of MethodSyncOrAsyncNoParam. That would indicate it is a PyCharm bug, not one for which we should introduce a new overload for all users.