Fix missing tox in the requirement file
Fix missing tox in the requirement file

TrivialFix

Change-Id: If59a0bf60d8de893e81c5aa2a579b316e5b24159

openstack/kuryr,midonet/kuryr,midonet/kuryr,celebdor/kuryr-libnetwork,openstack/kuryr,celebdor/kuryr,celebdor/kuryr,celebdor/kuryr-libnetwork,midonet/kuryr,celebdor/kuryr-libnetwork