Correct branch filter for publication job.

* modules/openstack_project/files/zuul/layout.yaml: The branch
filter for the infra-publications-publish job was missing a
wildcard, causing it not to match any branch at all. This fixes the
pattern to match the branches intended.

Change-Id: If3043ae5a17bbc6dd564689ec02622db9176d770
Reviewed-on: https://review.openstack.org/35903
Reviewed-by: Monty Taylor <mordred@inaugust.com>
Approved: James E. Blair <corvus@inaugust.com>
Reviewed-by: James E. Blair <corvus@inaugust.com>
Tested-by: Jenkins