Migrate jobs from CentOS 8 to CentOS 8 Stream

CentOS 8 is being removed from CI because of its EOL[1].

[1] http://lists.openstack.org/pipermail/openstack-discuss/2022-January/026621.html

Change-Id: I5867be3e61121891a66f076c922a32bd586dc428

.zuul.yaml

@@ -55,7 +55,7 @@
     name: cinderlib-lvm-functional
     parent: cinderlib-functional
     pre-run: playbooks/setup-lvm.yaml
-    nodeset: centos-8
+    nodeset: centos-8-stream
     vars:
       tox_environment:
         # Workaround for https://github.com/pypa/pip/issues/6264