[ci] Move use master containers to pre_deploy hook

This hook runs before the controlplanae is deployed, instead of after.
This _should_ reduce the runtime of the builds by avoiding the need to
wait for the changes to the openstackversions to be reconciled.

Author: elfiesmelfie

ci/vars-use-master-containers.yml

@@ -1,4 +1,4 @@
 ---
-post_ctlplane_deploy_99_modify_openstackversions:
+pre_deploy_99_modify_openstackversions:
   source: "{{ ansible_user_dir }}/{{ zuul.projects['github.com/infrawatch/feature-verification-tests'].src_dir }}/ci/use-master-containers.yml"
   type: playbook