Comment 3 for bug 1802182

I'm adding a new task for neutron-gateway where we are seeing the same root cause for a different stack trace:

2018-11-06 19:25:51 DEBUG openstack-upgrade Traceback (most recent call last):
2018-11-06 19:25:51 DEBUG openstack-upgrade File "/var/lib/juju/agents/unit-neutron-gateway-1/charm/actions/openstack-upgrade", line 10, in <module>
2018-11-06 19:25:51 DEBUG openstack-upgrade from neutron_utils import (
2018-11-06 19:25:51 DEBUG openstack-upgrade File "hooks/neutron_utils.py", line 29, in <module>
2018-11-06 19:25:51 DEBUG openstack-upgrade from charmhelpers.contrib.network.ovs import (
2018-11-06 19:25:51 DEBUG openstack-upgrade ImportError: cannot import name 'enable_ipfix'