Fix unmaintained branch CI

Zed is now call `unmaintained/zed` not `stable/zed`
This is requred for unmaintained/zed CI in Cinder.

NOTE(elod.illes): cinderlib is retired, hence the repository is empty
on master branch, causing issues with build-openstack-releasenotes job,
which should run on master. To unblock the gate this job (actually,
release-notes-jobs-python3 job template) needs to be dropped.

NOTE(elod.illes): centos-8-stream nodeset is removed from zuul config,
let's replace it with centos-9-stream in cinderlib-lvm-functional as
that OS is still supported. Also, set it as non-voting in check queue
and remove from gate queue to not block the gate.

NOTE(elod.illes): the following patch is also incorporated to unblock
the gate: Cap setuptools <71.0.0

py38 jobs (on ubuntu-focal) started to fail (see the relevant github
issue [1]) due to recent virtualenv release (20.26.4; which bundles
setuptools).

setuptools is bundled in virtualenv, so it has to be capped via the
virtualenv package. tox also needed to be capped (<4) as gate uses
tox 3.28.0, but with capping virtualenv we pull in latest tox as well,
which would cause other errors.

[1] https://github.com/pypa/setuptools/issues/4483

Conflicts:
  tox.ini

Change-Id: If769d9da92b724d40f47c9a57a75c021809c8850
(cherry picked from commit 6210535b90)
(cherry picked from commit 6ad87cbbe8)
(cherry picked from commit 1546df9246)
(cherry picked from commit 592cc260c9)

.zuul.yaml

@@ -2,14 +2,14 @@
     queue: integrated
     templates:
       - publish-openstack-docs-pti
-      - release-notes-jobs-python3
     check:
       jobs:
         - openstack-tox-pep8
         - cinderlib-tox-py36
         - cinderlib-tox-py37
 
-        - cinderlib-lvm-functional
+        - cinderlib-lvm-functional:
+            voting: false
         - cinderlib-ceph-functional
         - os-brick-src-tempest-lvm-lio-barbican
     gate:
@@ -18,7 +18,6 @@
         - cinderlib-tox-py36
         - cinderlib-tox-py37
 
-        - cinderlib-lvm-functional
         - cinderlib-ceph-functional
         - os-brick-src-tempest-lvm-lio-barbican
     post:
@@ -54,7 +53,7 @@
     name: cinderlib-lvm-functional
     parent: cinderlib-functional
     pre-run: playbooks/setup-lvm.yaml
-    nodeset: centos-8-stream
+    nodeset: centos-9-stream
     vars:
       tox_environment:
         # Workaround for https://github.com/pypa/pip/issues/6264

tox.ini

@@ -7,6 +7,12 @@ setenv = VIRTUAL_ENV={envdir}
 # this allows tox to infer the base python from the environment name
 # and override any basepython configured in this file
 ignore_basepython_conflict=true
+# Cap setuptools via virtualenv to prevent compatibility issue with yoga
+# branch's upper constraint of 'packaging' package (21.3).
+requires =
+  virtualenv<20.26.4
+  tox<4
+  setuptools<71.0.0
 
 [testenv]
 basepython=python3