Don't run requirements gate check job on stable/.
Don't run requirements gate check job on stable/.

At least until we figure out how we want to handle that
in the requirements repo.

Change-Id: I595078cfe63098062538c2587e3c229131bef55a
Reviewed-on: https://review.openstack.org/26760
Approved: James E. Blair <e81a02a9d6405977f63a769d9f6ec8ed9d924325@inaugust.com>
Reviewed-by: James E. Blair <e81a02a9d6405977f63a769d9f6ec8ed9d924325@inaugust.com>
Tested-by: Jenkins

noorul/os-project-config,Tesora/tesora-project-config,noorul/os-project-config,coolsvap/project-config,open-switch/infra_project-config,anbangr/osci-project-config,osrg/project-config,Tesora/tesora-project-config,open-switch/infra_project-config,anbangr/osci-project-config,openstack-infra/project-config,dongwenjuan/project-config,dongwenjuan/project-config,citrix-openstack/project-config,coolsvap/project-config,osrg/project-config,citrix-openstack/project-config,openstack-infra/project-config