infra-prod: override checkout on periodic/hourly

This override is already done in system-config, but it makes more
sense to do it here in the generic job.

Change-Id: If47d2068b02cc868b03dfe7ceb254c7d1ecf9d9b

playbooks/infra-prod/pre.yaml

@@ -43,3 +43,17 @@
     - name: Synchronize src repos to workspace directory.
       include_role:
         name: prepare-workspace-git
+
+    # When running from periodic/hourly we want to explicitly override
+    # to run from the tip of master
+    - name: Should we run from master
+      set_fact:
+        infra_prod_run_from_master: "{{ zuul.pipeline|default('') in ['periodic', 'opendev-prod-hourly'] }}"
+
+    - name: Update from master
+      when: infra_prod_run_from_master|bool
+      git:
+        repo: https://opendev.org/opendev/system-config
+        dest: /home/zuul/src/opendev.org/opendev/system-config
+        force: yes
+        version: master