### 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.
@task_decorator(multiple_outputs=True)
        def empty_dict():
            return {}
        with self.dag:
            ret = empty_dict()
        dr = self.create_dag_run()
        ret.operator.run(start_date=DEFAULT_DATE, end_date=DEFAULT_DATE)
        ti = dr.get_task_instances()[0]
        assert ti.xcom_pull() == {}
    def test_python_callable_arguments_are_templatized(self):
        """Test @task op_args are templatized"""
        @task_decorator
        def arg_task(*args):
            raise RuntimeError("Should not executed")
        
        
        Named = namedtuple("Named", ["var1", "var2"])
        named_tuple = Named("{{ ds }}", "unchanged")
        with self.dag:
            ret = arg_task(4, date(2019, 1, 1), "dag {{dag.dag_id}} ran on {{ds}}.", named_tuple)
        dr = self.create_dag_run()
        ti = TaskInstance(task=ret.operator, run_id=dr.run_id)
        rendered_op_args = ti.render_templates().op_args
        assert len(rendered_op_args) == 4
        assert rendered_op_args[0] == 4
        assert rendered_op_args[1] == date(2019, 1, 1)
        assert rendered_op_args[2] == f"dag {self.dag_id} ran on {self.ds_templated}."
        assert rendered_op_args[3] == Named(self.ds_templated, "unchanged")
    def test_python_callable_keyword_arguments_are_templatized(self):