Merge "Add Python3 xena unit tests"

Author: Zuul

.zuul.yaml

@@ -222,7 +222,7 @@
       - osc-tox-unit-tips
       - openstack-cover-jobs
       - openstack-lower-constraints-jobs
-      - openstack-python3-wallaby-jobs
+      - openstack-python3-xena-jobs
       - publish-openstack-docs-pti
       - check-requirements
       - release-notes-jobs-python3