koschei: run jobs with admin DB credentials

roles/openshift-apps/koschei/templates/config-admin.cfg.j2

@@ -8,6 +8,7 @@ config = {
         "username": "{{ koschei_pgsql_admin_username }}",
         "password": "{{ koschei_pgsql_admin_password }}",
     },
+    "unpriv_db_username": "{{ koschei_pgsql_username }}",
 }
 
 # Local Variables:

roles/openshift-apps/koschei/templates/job.yml

@@ -28,7 +28,7 @@ spec:
       volumes:
         - name: config
           secret:
-            secretName: backend-config
+            secretName: admin-config
         - name: keytab
           secret:
             secretName: keytab