ServerShowV263Test.test_show_update_rebuild_list_server fails cells v1 job with "ValueError: An object of type nova.objects.instance.TrustedCerts is required in field trusted_certs, not a dict"

Seen here:

http://logs.openstack.org/01/571201/1/gate/nova-cells-v1/56392c6/logs/screen-n-cell-child.txt.gz?level=TRACE#_Jun_18_14_14_15_307670

The new tempest test is using 2.63 with trusted certs for rebuild which isn't supported with cells v1.

Jun 18 14:14:15.307670 ubuntu-xenial-inap-mtl01-0000198149 nova-cells[27973]: ERROR nova.cells.scheduler [None req-063f2ef6-8896-4729-a287-31c50499b95f tempest-ServerShowV263Test-2087094943 tempest-ServerShowV263Test-2087094943] Couldn't communicate with cell 'child': ValueError: An object of type nova.objects.instance.TrustedCerts is required in field trusted_certs, not a dict
Jun 18 14:14:15.308000 ubuntu-xenial-inap-mtl01-0000198149 nova-cells[27973]: ERROR nova.cells.scheduler Traceback (most recent call last):
Jun 18 14:14:15.308248 ubuntu-xenial-inap-mtl01-0000198149 nova-cells[27973]: ERROR nova.cells.scheduler File "/opt/stack/new/nova/nova/cells/scheduler.py", line 177, in _build_instances
Jun 18 14:14:15.308494 ubuntu-xenial-inap-mtl01-0000198149 nova-cells[27973]: ERROR nova.cells.scheduler image, security_groups, block_device_mapping)
Jun 18 14:14:15.309087 ubuntu-xenial-inap-mtl01-0000198149 nova-cells[27973]: ERROR nova.cells.scheduler File "/opt/stack/new/nova/nova/cells/scheduler.py", line 96, in _create_instances_here
Jun 18 14:14:15.309390 ubuntu-xenial-inap-mtl01-0000198149 nova-cells[27973]: ERROR nova.cells.scheduler instance.update(instance_values)
Jun 18 14:14:15.309652 ubuntu-xenial-inap-mtl01-0000198149 nova-cells[27973]: ERROR nova.cells.scheduler File "/usr/local/lib/python2.7/dist-packages/oslo_versionedobjects/base.py", line 790, in update
Jun 18 14:14:15.309912 ubuntu-xenial-inap-mtl01-0000198149 nova-cells[27973]: ERROR nova.cells.scheduler setattr(self, key, value)
Jun 18 14:14:15.310183 ubuntu-xenial-inap-mtl01-0000198149 nova-cells[27973]: ERROR nova.cells.scheduler File "/usr/local/lib/python2.7/dist-packages/oslo_versionedobjects/base.py", line 72, in setter
Jun 18 14:14:15.310415 ubuntu-xenial-inap-mtl01-0000198149 nova-cells[27973]: ERROR nova.cells.scheduler field_value = field.coerce(self, name, value)
Jun 18 14:14:15.310738 ubuntu-xenial-inap-mtl01-0000198149 nova-cells[27973]: ERROR nova.cells.scheduler File "/usr/local/lib/python2.7/dist-packages/oslo_versionedobjects/fields.py", line 195, in coerce
Jun 18 14:14:15.311043 ubuntu-xenial-inap-mtl01-0000198149 nova-cells[27973]: ERROR nova.cells.scheduler return self._type.coerce(obj, attr, value)
Jun 18 14:14:15.311344 ubuntu-xenial-inap-mtl01-0000198149 nova-cells[27973]: ERROR nova.cells.scheduler File "/usr/local/lib/python2.7/dist-packages/oslo_versionedobjects/fields.py", line 799, in coerce
Jun 18 14:14:15.311642 ubuntu-xenial-inap-mtl01-0000198149 nova-cells[27973]: ERROR nova.cells.scheduler obj_name])})
Jun 18 14:14:15.311995 ubuntu-xenial-inap-mtl01-0000198149 nova-cells[27973]: ERROR nova.cells.scheduler ValueError: An object of type nova.objects.instance.TrustedCerts is required in field trusted_certs, not a dict
Jun 18 14:14:15.312279 ubuntu-xenial-inap-mtl01-0000198149 nova-cells[27973]: ERROR nova.cells.scheduler

http://logstash.openstack.org/#dashboard/file/logstash.json?query=message%3A%5C%22Couldn't%20communicate%20with%20cell%20'child'%3A%20ValueError%3A%20An%20object%20of%20type%20nova.objects.instance.TrustedCerts%20is%20required%20in%20field%20trusted_certs%2C%20not%20a%20dict%5C%22%20AND%20tags%3A%5C%22screen-n-cell-child.txt%5C%22&from=7d

275 hits in 24 hours, all failures.

We need to just skip the test in the cells v1 job:

https://review.openstack.org/#/c/576194/