switch documentation job to new PTI

This is a mechanically generated patch to switch the documentation
jobs to use the new PTI versions of the jobs as part of the
python3-first goal.

See the python3-first goal document for details:
https://governance.openstack.org/tc/goals/stein/python3-first.html

Change-Id: Iee24afd0da25751b7b2f8ec073066bcc7ebd5f5c
Story: #2002586
Task: #24321

.zuul.yaml

@@ -217,11 +217,11 @@
 - project:
     templates:
       - publish-to-pypi
-      - publish-openstack-sphinx-docs
+      - publish-openstack-docs-pti
       - shade-functional-tips
       - shade-tox-tips
       - openstack-python-jobs
-      - release-notes-jobs
+      - release-notes-jobs-python3
       - check-requirements
       - openstack-python35-jobs
     check: