### Apache Airflow version

2.2.0b2 (beta snapshot)

### Operating System

ubuntu 20.04

### Versions of Apache Airflow Providers

n/a

### Deployment

Virtualenv installation

### Deployment details

pip install /path/to/airflow/src

### What happened

Given any DAG initialized with: `schedule_interval=None`

Run `airflow dags test mydagname $(date +%Y-%m-%d)` and get an error:

```
INFO - No run dates were found for the given dates and dag interval.
```

This behavior changed in https://github.com/apache/airflow/pull/15397, it used to trigger a backfill dagrun at the given date.

### What you expected to happen

I expected a backfill dagrun with the given date, regardless of whether it fit into the `schedule_interval`.

If AIP-39 made that an unrealistic expectation, then I'd hope for some way to define unscheduled dags which can still be tested from the command line (which, so far as I know, is the fastest way to iterate on a DAG.).

As it is, I keep changing `schedule_interval` back and forth depending on whether I want to iterate via `astro dev start` (which tolerates `None` but does superfluous work if the dag is scheduled) or via `airflow dags test ...` (which doesn't tolerate `None`).

### How to reproduce

Initialize a DAG with: `schedule_interval=None` and run it via `airflow dags test mydagname $(date +%Y-%m-%d)`

### 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)

airflow/models/dag.py
warnings.warn(
            "The 'DAG.concurrency' attribute is deprecated. Please use 'DAG.max_active_tasks'.",
            DeprecationWarning,
            stacklevel=2,
        )
        return self._max_active_tasks
    @concurrency.setter
    def concurrency(self, value: int):
        self._max_active_tasks = value
    @property
    def max_active_tasks(self) -> int:
        return self._max_active_tasks
    @max_active_tasks.setter
    def max_active_tasks(self, value: int):
        self._max_active_tasks = value
    @property
    def access_control(self):
        return self._access_control
    @access_control.setter
    def access_control(self, value):
        self._access_control = DAG._upgrade_outdated_dag_access_control(value)
    @property
    def description(self) -> Optional[str]:
        return self._description
    @property
    def default_view(self) -> str: