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.

"""Process form data."""
        conn_id = form.data["conn_id"]
        conn_type = form.data["conn_type"]
        
        
        
        extra = {}
        extra_json = form.data.get("extra")
        if extra_json:
            try:
                extra.update(json.loads(extra_json))
            except (JSONDecodeError, TypeError):
                flash(
                    Markup(
                        "<p>The <em>Extra</em> connection field contained an invalid value for Conn ID: "
                        "<q>{conn_id}</q>.</p>"
                        "<p>If connection parameters need to be added to <em>Extra</em>, "
                        "please make sure they are in the form of a single, valid JSON object.</p><br>"
                        "The following <em>Extra</em> parameters were <b>not</b> added to the connection:<br>"
                        "{extra_json}"
                    ).format(conn_id=conn_id, extra_json=extra_json),
                    category="error",
                )
                del form.extra
        del extra_json
        for key, field_name in self._iter_extra_field_names():
            if key in form.data and key.startswith("extra__"):
                conn_type_from_extra_field = key.split("__")[1]