### Body

Currently when you use multiple-outputs in decorator and it gets None value, it crashes.

As explained in https://github.com/apache/airflow/issues/32553 and workaround for ShortCircuitOperator has been implemented here:  https://github.com/apache/airflow/pull/32569 

But a more complete fix for multiple-outputs handling None is needed. 

### Committer

- [X] I acknowledge that I am a maintainer/committer of the Apache Airflow project.
if "return" not in self.function.__annotations__:
            
            return False
        try:
            
            def fake():
                ...
            fake.__annotations__ = {"return": self.function.__annotations__["return"]}
            return_type = typing_extensions.get_type_hints(fake, self.function.__globals__).get("return", Any)
        except NameError as e:
            warnings.warn(
                f"Cannot infer multiple_outputs for TaskFlow function {self.function.__name__!r} with forward"
                f" type references that are not imported. (Error was {e})",
                stacklevel=4,
            )
            return False
        except TypeError:  
            return False
        ttype = getattr(return_type, "__origin__", return_type)
        return ttype == dict or ttype == Dict
    def __attrs_post_init__(self):