Unable to freeze job graph: Unable to modify final job <Job publish-openstack-releasenotes branches: None source: openstack-infra/project-config/zuul.d/jobs.yaml@master#218> attribute required_projects={'openstack/horizon': <zuul.model.JobProject object at 0x7fd45ccded30>} with variant <Job publish-openstack-releasenotes branches: None source: openstack-infra/openstack-zuul-jobs/zuul.d/project-templates.yaml@master#267>