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.

return not (
                attr_name == "HIDE_ATTRS_FROM_UI"
                or attr_name.startswith("_")
                or attr_name in attr_renderers
                or attr_name in attrs_to_skip
            )
        task_attrs = [
            (attr_name, secrets_masker.redact(attr, attr_name))
            for attr_name, attr in (
                (attr_name, getattr(task, attr_name)) for attr_name in filter(include_task_attrs, dir(task))
            )
            if not callable(attr)
        ]
        
        special_attrs_rendered = {
            attr_name: renderer(getattr(task, attr_name))
            for attr_name, renderer in attr_renderers.items()
            if hasattr(task, attr_name)
        }
        no_failed_deps_result = [
            (
                "Unknown",