The only place where it stays is argument parsing where it gets ignored.
Hardcoded to 'source' to make merging both kolla and kolla-ansible
changes easier.
Change-Id: I6890a7ec7baf507f8acd75b42bbd0fb17c2e4511
Depends-On: https://review.opendev.org/c/openstack/kolla-ansible/+/837620