Run jobs prod test jobs when docker images update

We build our own docker images for several services, but weren't
triggering production test runs when the docker images are updated. Fix
this and force chagnes to dockerfiles, which produce new images, to
trigger production test runs of those services.

Change-Id: I18962663f168bbf6380e315d96b18751a46ceb58

zuul.d/system-config-run.yaml

@@ -547,6 +547,7 @@
       - playbooks/roles/install-docker/
       - playbooks/zuul/templates/group_vars/meetpad.yaml.j2
       - testinfra/test_meetpad.py
+      - docker/jitsi-meet/
 
 - job:
     name: system-config-run-zookeeper
@@ -694,6 +695,7 @@
       - playbooks/zuul/templates/group_vars/review-dev.yaml.j2
       - playbooks/zuul/templates/group_vars/review.yaml.j2
       - testinfra/test_gerrit.py
+      - docker/gerrit/2.13/
 
 - job:
     name: system-config-run-static