Use the UBI8 image for testing

This change converts our use of CentOS7/88 to UBI8, which should
provide a better test environment which will match that of
production for future releases of TripleO. While this image change
will better match production clouds thanks in large part to TCIB,
it will also remove our use of docker.io (dockerhub) which fraught
with peril due to the ongoing API rate limits saga.

Story: 2006061
Task: 34774

Change-Id: I067046e5fd4d56cd88712f553e25a61db60ced7f
Signed-off-by: Kevin Carter <kecarter@redhat.com>

tripleo_ansible/roles/tripleo_clients_install/molecule/default/molecule.yml

@@ -5,34 +5,32 @@ driver:
 log: true
 
 platforms:
-  - name: centos7
-    hostname: centos7
-    image: centos:7
+  - name: ubi8
+    hostname: ubi8
+    image: ubi8/ubi-init
+    registry:
+      url: registry.access.redhat.com
     dockerfile: Dockerfile
-    pkg_extras: python-setuptools
+    pkg_extras: python*setuptools
     volumes:
       - /etc/ci/mirror_info.sh:/etc/ci/mirror_info.sh:ro
-    easy_install:
-      - pip
+      - /etc/pki/rpm-gpg:/etc/pki/rpm-gpg
+      - /opt/yum.repos.d:/etc/yum.repos.d:rw
+    privileged: true
     environment: &env
       http_proxy: "{{ lookup('env', 'http_proxy') }}"
       https_proxy: "{{ lookup('env', 'https_proxy') }}"
     ulimits: &ulimit
       - host
 
-  - name: centos8
-    hostname: centos8
-    image: centos:8
-    dockerfile: Dockerfile
-    pkg_extras: python*-setuptools
-    volumes:
-      - /etc/ci/mirror_info.sh:/etc/ci/mirror_info.sh:ro
-    environment:
-      <<: *env
-    ulimits: *ulimit
-
 provisioner:
   name: ansible
+  inventory:
+    hosts:
+      all:
+        hosts:
+          ubi8:
+            ansible_python_interpreter: /usr/bin/python3
   log: true
   env:
     ANSIBLE_STDOUT_CALLBACK: yaml