Add Python3 master unit tests

This is an automatically generated patch to ensure unit testing
is in place for all the of the tested runtimes for victoria.

See also the PTI in governance [1].

[1]: https://governance.openstack.org/tc/reference/project-testing-interface.html

Change-Id: I7465f908f4f632d7615df52f1c34f30fee0b0b9f

zuul.d/projects.yaml

@@ -6,7 +6,7 @@
       - periodic-stable-jobs-neutron
       - openstack-cover-jobs
       - openstack-lower-constraints-jobs
-      - openstack-python3-ussuri-jobs
+      - openstack-python3-victoria-jobs
       - publish-openstack-docs-pti
       - release-notes-jobs-python3
       - octavia-tox-tips