### 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
with create_session() as session:
            session.add(DagModel(dag_id='dag_default_view_old', default_view=None))
            session.commit()
            orm_dag = session.query(DagModel).filter(DagModel.dag_id == 'dag_default_view_old').one()
        assert orm_dag.default_view is None
        assert orm_dag.get_default_view() == conf.get('webserver', 'dag_default_view').lower()
    def test_dag_is_deactivated_upon_dagfile_deletion(self):
        dag_id = 'old_existing_dag'
        dag_fileloc = "/usr/local/airflow/dags/non_existing_path.py"
        dag = DAG(
            dag_id,
            is_paused_upon_creation=True,
        )
        dag.fileloc = dag_fileloc
        session = settings.Session()
        with mock.patch('airflow.models.dag.DagCode.bulk_sync_to_db'):
            dag.sync_to_db(session=session)
        orm_dag = session.query(DagModel).filter(DagModel.dag_id == dag_id).one()
        assert orm_dag.is_active
        assert orm_dag.fileloc == dag_fileloc
        DagModel.deactivate_deleted_dags(list_py_file_paths(settings.DAGS_FOLDER))
        orm_dag = session.query(DagModel).filter(DagModel.dag_id == dag_id).one()
        assert not orm_dag.is_active
        session.execute(DagModel.__table__.delete().where(DagModel.dag_id == dag_id))
        session.close()
    def test_dag_naive_default_args_start_date_with_timezone(self):