Remove tripleo CI jobs

This role was shared with tripleo, but that project is now
deprecated so there is no need to carry the cross-project CI jobs
any more.

Change-Id: I73aec0f325708f42bbd0fd07d572fb833e8dfb2c

zuul.d/project.yaml

@@ -21,27 +21,3 @@
       - openstack-ansible-deploy-aio_distro_metal-jobs
       - publish-openstack-docs-pti
       - build-release-notes-jobs-python3
-    check:
-      jobs:
-        - openstack-ansible-deploy-aio_distro_metal_tempestconf-centos-8-stream
-        - tripleo-ci-centos-9-content-provider
-        - openstack-tox-molecule:
-            voting: false
-            vars:
-              tox_environment:
-                PYTEST_REQPASS: 1
-        - tripleo-ci-centos-9-standalone:
-            vars: &consumer_vars
-              consumer_job: true
-              build_container_images: false
-              remove_tags:
-                - build
-            dependencies:
-              - tripleo-ci-centos-9-content-provider
-    gate:
-      jobs:
-        - tripleo-ci-centos-9-content-provider
-        - tripleo-ci-centos-9-standalone:
-            vars: *consumer_vars
-            dependencies:
-              - tripleo-ci-centos-9-content-provider