import zuul job settings from project-config

This is a mechanically generated patch to complete step 1 of moving
the zuul job settings out of project-config and into each project
repository.

Because there will be a separate patch on each branch, the branch
specifiers for branch-specific jobs have been removed.

Because this patch is generated by a script, there may be some
cosmetic changes to the layout of the YAML file(s) as the contents are
normalized.

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

Introduce a minor change to the guide's build configuration file in
order to trigger the jobs and allow the patch to be tested.

Fix .gitreview file.

Change-Id: I4fed6e402a19a616fb8b30c1d07e704b34b866dc
Story: #2002586
Task: #24317

.gitreview

@@ -2,3 +2,4 @@
 host=review.openstack.org
 port=29418
 project=openstack/charm-deployment-guide.git
+defaultbranch=stable/rocky

.zuul.yaml

@@ -0,0 +1,3 @@
+- project:
+    templates:
+      - deploy-guide-jobs

deploy-guide/source/conf.py

@@ -21,8 +21,6 @@
 # serve to show the default.
 
 import os
-# import sys
-
 
 import openstackdocstheme