test_list_server_addresses fails under swift gate job

[Peter Portante]

See: http://logs.openstack.org/95/44895/3/check/gate-tempest-devstack-vm-neutron/8f3db63/console.html

2013-09-06 22:27:42.925 | ======================================================================
2013-09-06 22:27:42.926 | FAIL: tempest.api.compute.servers.test_server_addresses.ServerAddressesTestXML.test_list_server_addresses[gate,smoke]
2013-09-06 22:27:42.926 | tempest.api.compute.servers.test_server_addresses.ServerAddressesTestXML.test_list_server_addresses[gate,smoke]
2013-09-06 22:27:42.926 | ----------------------------------------------------------------------
2013-09-06 22:27:42.926 | _StringException: Empty attachments:
2013-09-06 22:27:42.926 | stderr
2013-09-06 22:27:42.926 | stdout
2013-09-06 22:27:42.927 |
2013-09-06 22:27:42.927 | pythonlogging:'': {{{
2013-09-06 22:27:42.927 | 2013-09-06 22:22:15,385 Request: GET http://127.0.0.1:8774/v2/aa5250d0ca7d4c9f9728cc3fd0341add/servers/047fe71f-b85d-4762-b201-7aa8084ff32c/ips
2013-09-06 22:27:42.927 | 2013-09-06 22:22:15,428 Response Status: 200
2013-09-06 22:27:42.927 | 2013-09-06 22:22:15,429 Nova request id: req-201094ad-e0f8-451b-a744-8c81b98bdf0b
2013-09-06 22:27:42.927 | }}}
2013-09-06 22:27:42.928 |
2013-09-06 22:27:42.928 | Traceback (most recent call last):
2013-09-06 22:27:42.928 | File "tempest/api/compute/servers/test_server_addresses.py", line 56, in test_list_server_addresses
2013-09-06 22:27:42.928 | self.assertTrue(len(addresses) >= 1)
2013-09-06 22:27:42.928 | File "/usr/lib/python2.7/unittest/case.py", line 420, in assertTrue
2013-09-06 22:27:42.928 | raise self.failureException(msg)
2013-09-06 22:27:42.929 | AssertionError: False is not true