Improve test coverage: server secgroup API
Improve test coverage: server secgroup API

Change-Id: I4556128548dec0bfed141db4a22e35e954a46f45

openstack-infra/shade,dtroyer/python-openstacksdk,dtroyer/python-openstacksdk,stackforge/python-openstacksdk,openstack-infra/shade,openstack/python-openstacksdk,stackforge/python-openstacksdk,openstack/python-openstacksdk