There's only fake unit test for tacker-horizon

Currently, there's only fake test to bypass in tacker-horizon. For example, this is the only test case for vnfmanager:

tacker_horizon/openstack_dashboard/dashboards/nfv/vnfmanager/tests.py

...
class VnfmanagerTests(test.TestCase):
    # Unit tests for vnfmanager.
    def test_me(self):
        self.assertTrue(1 + 1 == 2)