Cleanup instance ha dir as root

Without become=true FFU would fail with:

FATAL | Ensure instanceha directory is purged | compute-1 | error={"changed": false, "msg": "rmtree failed: [Errno 13] Permission denied: 'check-run-nova-compute'"}

Change-Id: I9b25063dded49fa5dae589fba627b2dbdccb17f6

deployment/nova/nova-compute-container-puppet.yaml

@@ -1777,12 +1777,14 @@ outputs:
       post_update_tasks:
         - name: Ensure instanceha directory is purged
           when: step|int == 1
+          become: true
           file:
             path: /var/lib/nova/instanceha
             state: absent
       post_upgrade_tasks:
         - name: Ensure instanceha directory is purged
           when: step|int == 1
+          become: true
           file:
             path: /var/lib/nova/instanceha
             state: absent