Fix gate failures for Docker and Pep8

- Zuul updated ansible to 2.7, no longer uses missing variables.
- Using an if to try and address.
- Fixes a few formatting problems that are causing the gates to fail

Docker fix based on Aaron Sheffield's PS for Pegleg:
https://review.openstack.org/#/c/645631/

Change-Id: I14e8f3aac0af7a3abc4e2b6c4ece292a24bc4c6a

armada/tests/unit/handlers/test_armada.py

@@ -356,10 +356,8 @@ class ArmadaHandlerTestCase(base.ArmadaTestCase):
             if test_failure_to_run:
 
                 def fail(tiller, release, timeout=None, cleanup=False):
-                    status = AttrDict(**{
-                        'info':
-                        AttrDict(**{'Description': 'Failed'})
-                    })
+                    status = AttrDict(
+                        **{'info': AttrDict(**{'Description': 'Failed'})})
                     raise tiller_exceptions.ReleaseException(
                         release, status, 'Test')
 

armada/tests/unit/handlers/test_tiller.py

@@ -535,8 +535,8 @@ class TillerTestCase(base.ArmadaTestCase):
                     AttrDict(
                         **{
                             'status':
-                            AttrDict(**
-                                     {'last_test_suite_run': test_suite_run}),
+                            AttrDict(
+                                **{'last_test_suite_run': test_suite_run}),
                             'Description':
                             'Failed'
                         })

tools/gate/playbooks/docker-image-build.yaml

@@ -32,7 +32,7 @@
       environment:
         BRANCH: "{{ zuul.branch }}"
         CHANGE: "{{ zuul.change }}"
-        COMMIT: "{{ zuul.newrev }}"
+        COMMIT: "{{ zuul.newrev | default('') }}"
         PATCHSET: "{{ zuul.patchset }}"
       register: image_tags
 
@@ -116,7 +116,7 @@
               DOCKER_REGISTRY: "quay.io"
               IMAGE_PREFIX: "airshipit"
               IMAGE_TAG: "{{ item }}"
-              COMMIT: "{{ zuul.newrev }}"
+              COMMIT: "{{ zuul.newrev | default('') }}"
               PUSH_IMAGE: "true"
           with_items: "{{ image_tags.stdout_lines }}"