### Description

Recently, we added [a new DAG dependencies view](https://github.com/apache/airflow/pull/13199) to the webserver. It would be helpful if a similar diagram could also be displayed/generated using the CLI. For now, only [one DAG can be displayed](http://airflow.apache.org/docs/apache-airflow/stable/usage-cli.html#exporting-dag-structure-as-an-image) using CLI.
![image](https://user-images.githubusercontent.com/12058428/137945580-6a33f919-2648-4980-bd2c-b40cfcacc9fe.png)

If anyone is interested, I will be happy to help with the review.

### Use case/motivation

* Keep parity between CLI and web serwer.
* Enable the writing of scripts that use these diagrams, e.g. for attaching in the documentation.

### Related issues

https://github.com/apache/airflow/pull/13199/files

### Are you willing to submit a 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/utils/dot_renderer.py
"""Draw a single task on the given parent_graph"""
    if states_by_task_id:
        state = states_by_task_id.get(task.task_id, State.NONE)
        color = State.color_fg(state)
        fill_color = State.color(state)
    else:
        color = task.ui_fgcolor
        fill_color = task.ui_color
    parent_graph.node(
        task.task_id,
        _attributes={
            "label": task.label,
            "shape": "rectangle",
            "style": "filled,rounded",
            "color": _refine_color(color),
            "fillcolor": _refine_color(fill_color),
        },
    )
def _draw_task_group(
    task_group: TaskGroup, parent_graph: graphviz.Digraph, states_by_task_id: Dict[str, str]
) -> None:
    """Draw the given task_group and its children on the given parent_graph"""