Add Python3 zed unit tests

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

See also the PTI in governance [1].

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

Change-Id: I8fec4859616a14c334abf04b1075d63fecec4134

zuul.d/projects.yaml

@@ -4,7 +4,7 @@
       - horizon-non-primary-django-jobs
       - horizon-nodejs14-jobs
       - openstack-lower-constraints-jobs
-      - openstack-python3-yoga-jobs-horizon
+      - openstack-python3-zed-jobs-horizon
       - publish-openstack-docs-pti
       - release-notes-jobs-python3
     gate: