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.

dag = get_airflow_app().dag_bag.get_dag(dag_id)
            if dag:
                ti.task = dag.get_task(ti.task_id)
            if response_format == "json":
                logs, metadata = task_log_reader.read_log_chunks(ti, try_number, metadata)
                message = logs[0] if try_number is not None else logs
                return {"message": message, "metadata": metadata}
            metadata["download_logs"] = True
            attachment_filename = task_log_reader.render_log_filename(ti, try_number, session=session)
            log_stream = task_log_reader.read_log_stream(ti, try_number, metadata)
            return Response(
                response=log_stream,
                mimetype="text/plain",
                headers={"Content-Disposition": f"attachment; filename={attachment_filename}"},
            )
        except AttributeError as e:
            error_messages = [f"Task log handler does not support read logs.\n{str(e)}\n"]
            metadata["end_of_log"] = True
            return {"message": error_messages, "error": True, "metadata": metadata}
    @expose("/log")
    @auth.has_access(
        [
            (permissions.ACTION_CAN_READ, permissions.RESOURCE_DAG),
            (permissions.ACTION_CAN_READ, permissions.RESOURCE_TASK_INSTANCE),
            (permissions.ACTION_CAN_READ, permissions.RESOURCE_TASK_LOG),
        ]
    )
    @action_logging
    @provide_session
    def log(self, session: Session = NEW_SESSION):