Add post step to Tempest base job

Stage three tempest conf and log files for archival using the
stage-output role.

Depends-on: Id45a50821539985710da7172a9185fd91e803603
Change-Id: Id67dbf3df5af52e848b8d378bc13aaa1c02cdd29
diff --git a/.zuul.yaml b/.zuul.yaml
index 5b73695..e646d9b 100644
--- a/.zuul.yaml
+++ b/.zuul.yaml
@@ -11,6 +11,7 @@
       devstack_services:
         tempest: True
     run: playbooks/devstack-tempest.yaml
+    post-run: playbooks/post-tempest.yaml
 
 - project:
     name: openstack/tempest