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.

"""View to provide autocomplete results."""
    @auth.has_access([(permissions.ACTION_CAN_READ, permissions.RESOURCE_DAG)])
    @provide_session
    @expose("/dagmodel/autocomplete")
    def autocomplete(self, session: Session = NEW_SESSION):
        """Autocomplete."""
        query = unquote(request.args.get("query", ""))
        if not query:
            return flask.json.jsonify([])
        
        dag_ids_query = session.query(
            sqla.literal("dag").label("type"),
            DagModel.dag_id.label("name"),
        ).filter(~DagModel.is_subdag, DagModel.is_active, DagModel.dag_id.ilike("%" + query + "%"))
        owners_query = (
            session.query(
                sqla.literal("owner").label("type"),
                DagModel.owners.label("name"),
            )
            .distinct()
            .filter(~DagModel.is_subdag, DagModel.is_active, DagModel.owners.ilike("%" + query + "%"))
        )
        
        status = flask_session.get(FILTER_STATUS_COOKIE)
        if status == "active":
            dag_ids_query = dag_ids_query.filter(~DagModel.is_paused)
            owners_query = owners_query.filter(~DagModel.is_paused)
        elif status == "paused":