puppet/periodic: export ZUUL_REF
puppet/periodic: export ZUUL_REF

In puppet-openstack-integration-checkout JJB builder, make sure we
export ZUUL_REF, otherwise periodic jobs will fail with this error:

> Provide either ZUUL_REF or BRANCH in the calling enviromnent
> git failed, retrying

Change-Id: Iff99aec747cd778d559b5092d91a46ad24a5c975

openstack-infra/project-config,openstack-infra/project-config,Tesora/tesora-project-config,dongwenjuan/project-config,Tesora/tesora-project-config,dongwenjuan/project-config