Don't run the tarball jobs for core projects on tags.
Don't run the tarball jobs for core projects on tags.

The tarball script isn't expecting a tag.

Change-Id: I374408ea0aa40ef68beffedeabaa0701b014cb7d
Reviewed-on: https://review.openstack.org/12968
Reviewed-by: Clark Boylan <635fc31d01fa593720982fa0568e87170cedbe2c@gmail.com>
Approved: Monty Taylor <37c07a49ee3d5191376d758eb1d8298b34456b8e@inaugust.com>
Reviewed-by: Monty Taylor <37c07a49ee3d5191376d758eb1d8298b34456b8e@inaugust.com>
Tested-by: Jenkins

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