As https://github.com/openstack/tempest/blob/master/releasenotes/notes/tempest-stein-release-18bad34136a2e6ef.yaml the latest Tempest doesn't support Ocata. So we need to use the tag of Ocata supported Tempest with https://github.com/openstack/tempest/releases/tag/20.0.0
As https:/ /github. com/openstack/ tempest/ blob/master/ releasenotes/ notes/tempest- stein-release- 18bad34136a2e6e f.yaml the latest Tempest doesn't support Ocata. /github. com/openstack/ tempest/ releases/ tag/20. 0.0
So we need to use the tag of Ocata supported Tempest with https:/