Remove ussuri jobs from the project's CI queues

As stable/ussuri just was switched to EM phase, we don't need to run
it's tests in the neutron-tempest-plugin CI.
Neutron-tempest-plugin is pinned to the 1.8.0 version in the ussuri
jobs and that will be used in e.g. Neutron stable/ussuri since now.

Depends-On: https://review.opendev.org/c/openstack/releases/+/818687
Change-Id: Ibba4bc4b383c5bd9d7301859538f5a24f9bb1883
2 files changed