### Apache Airflow version

2.2.0 (latest released)

### Operating System

Mac

### Versions of Apache Airflow Providers

_No response_

### Deployment

Other Docker-based deployment

### Deployment details

_No response_

### What happened

Getting an exception when returning None from next_dagrun_info in a custom timetable. The timetable protocol says that when None is returned a DagRun will not happen but right now it throws an exception.

Exception:
```
Traceback (most recent call last):
  File "/home/airflow/.local/lib/python3.9/site-packages/airflow/jobs/scheduler_job.py", line 623, in _execute
    self._run_scheduler_loop()
  File "/home/airflow/.local/lib/python3.9/site-packages/airflow/jobs/scheduler_job.py", line 704, in _run_scheduler_loop
    num_queued_tis = self._do_scheduling(session)
  File "/home/airflow/.local/lib/python3.9/site-packages/airflow/jobs/scheduler_job.py", line 787, in _do_scheduling
    callback_to_run = self._schedule_dag_run(dag_run, session)
  File "/home/airflow/.local/lib/python3.9/site-packages/airflow/jobs/scheduler_job.py", line 1039, in _schedule_dag_run
    self._update_dag_next_dagruns(dag, dag_model, active_runs)
  File "/home/airflow/.local/lib/python3.9/site-packages/airflow/jobs/scheduler_job.py", line 930, in _update_dag_next_dagruns
    data_interval = dag.get_next_data_interval(dag_model)
  File "/home/airflow/.local/lib/python3.9/site-packages/airflow/models/dag.py", line 629, in get_next_data_interval
    return self.infer_automated_data_interval(dag_model.next_dagrun)
  File "/home/airflow/.local/lib/python3.9/site-packages/airflow/models/dag.py", line 671, in infer_automated_data_interval
    raise ValueError(f"Not a valid timetable: {self.timetable!r}")
ValueError: Not a valid timetable: <my_timetables.workday_timetable.WorkdayTimetable object at 0x7f42b1f02430>
```

### What you expected to happen

DagRun to not happen.

### How to reproduce

Create a custom timetable and return None in next_dagrun_info after a few DagRuns are created by that timetable

### Anything else

_No response_

### Are you willing to submit PR?

- [ ] Yes I am willing to submit a PR!

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.md)

tests/models/test_dag.py
"""
            Create a subdag.
            """
            dag_subdag = DAG(
                dag_id=f'{parent_dag_name}.{child_dag_name}',
                schedule_interval="@daily",
                default_args=args,
            )
            for i in range(2):
                DummyOperator(task_id=f'{child_dag_name}-task-{i + 1}', dag=dag_subdag)
            return dag_subdag
        with DAG(
            dag_id='test_subdag_operator',
            start_date=datetime.datetime(2019, 1, 1),
            max_active_runs=1,
            schedule_interval=timedelta(minutes=1),
        ) as dag:
            section_1 = SubDagOperator(
                task_id='section-1',
                subdag=subdag(dag.dag_id, 'section-1', {'start_date': dag.start_date}),
            )
        subdag = section_1.subdag
        
        subdag.parent_dag = dag
        subdag.is_subdag = True
        next_parent_info = dag.next_dagrun_info(None)
        assert next_parent_info.logical_date == timezone.datetime(2019, 1, 1, 0, 0)
        next_subdag_info = subdag.next_dagrun_info(None)
        assert next_subdag_info is None, "SubDags should never have DagRuns created by the scheduler"
    def test_replace_outdated_access_control_actions(self):