Only run bandit when changing python content

This changes the gate check for bandit to only run when either python
or templated python files are edited. This will cause the check
to only be ran when those specific file types are edited, and to
skip the check when not needed.

Change-Id: I149ef6827ca10e32492f2b05beb8a13af5a03fc5

zuul.d/jobs-openstack-helm.yaml

@@ -30,13 +30,9 @@
     run: tools/gate/playbooks/osh-bandit.yaml
     required-projects:
       - openstack/openstack-helm-infra
-    # NOTE(gagehugo): Look into only running this for py.tpl file changes
-    # files:
-    #  - ^.*\.py\.tpl$
-    irrelevant-files:
-      - ^.*\.rst$
-      - ^doc/.*$
-      - ^releasenotes/.*$
+    files:
+      - ^.*\.py\.tpl$
+      - ^.*\.py$
 
 - job:
     name: openstack-helm-chart-deploy