The DAGs main page has All/Active/Paused.

It would be nice if we can have also Running Now which will show all the DAGs that have at least 1 in Running of DAG runs:
![Screen Shot 2021-08-25 at 11 30 55](https://user-images.githubusercontent.com/62940116/130756490-647dc664-7528-4eb7-b4d8-515577f7e6bb.png)


For the above example the new DAGs tab of Running Now should show only 2 rows.
The use case is to see easily what DAGs are currently in progress.

self,
        dag_id: str,
        dag_run_id: str,
        confirmed: bool,
        session: Session = NEW_SESSION,
    ):
        if not dag_run_id:
            return {"status": "error", "message": "Invalid dag_run_id"}
        dag = get_airflow_app().dag_bag.get_dag(dag_id)
        if not dag:
            return {"status": "error", "message": f"Cannot find DAG: {dag_id}"}
        set_dag_run_state_to_queued(dag=dag, run_id=dag_run_id, commit=confirmed)
        if confirmed:
            return {"status": "success", "message": "Marked the DagRun as queued."}
        else:
            
            all_task_ids = [task.task_id for task in dag.tasks]
            existing_tis = session.query(TaskInstance.task_id).filter(