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.

"""Base View to set Airflow related properties."""
    from airflow import macros
    route_base = ""
    extra_args = {
        
        "macros": macros,
        "get_docs_url": get_docs_url,
    }
    if not conf.getboolean("core", "unit_test_mode"):
        executor, _ = ExecutorLoader.import_default_executor_cls()
        extra_args["sqlite_warning"] = settings.engine.dialect.name == "sqlite"
        if not executor.is_production:
            extra_args["production_executor_warning"] = executor.__name__
        extra_args["otel_on"] = conf.getboolean("metrics", "otel_on")
    line_chart_attr = {
        "legend.maxKeyLength": 200,
    }
    def render_template(self, *args, **kwargs):