Remove unnecessary test extension mock
Remove unnecessary test extension mock

The network extension test does not need this.

Change-Id: I8dd2cad759a813d7df0476afa6c56f455ddff616

dtroyer/python-openstackclient,BjoernT/python-openstackclient,openstack/python-openstackclient,openstack/python-openstackclient,dtroyer/python-openstackclient,redhat-openstack/python-openstackclient,redhat-openstack/python-openstackclient,BjoernT/python-openstackclient