Remove unused centos-8 functional job definitions

Depends-On: https://review.opendev.org/c/openstack/ansible-role-qdrouterd/+/820672
Change-Id: I7c4ef5da667cc157a9d263477afa50b8eb73149c

test-ansible-collection-requirements.yml

@@ -24,3 +24,6 @@ collections:
   - name: openvswitch.openvswitch
     version: 2.0.2
     source: https://galaxy.ansible.com
+  - name: https://opendev.org/openstack/openstack-ansible-plugins
+    version: master
+    type: git

zuul.d/jobs.yaml

@@ -130,16 +130,9 @@
     nodeset: ubuntu-focal
 
 - job:
-    name: openstack-ansible-functional-centos-8
+    name: openstack-ansible-functional-centos-8-stream
     parent: openstack-ansible-functional
-    nodeset: centos-8
-
-- job:
-    name: openstack-ansible-functional-distro_install-centos-8
-    parent: openstack-ansible-functional
-    nodeset: centos-8
-    vars:
-      tox_env: distro_install
+    nodeset: centos-8-stream
 
 - job:
     name: openstack-ansible-cross-repo-functional

zuul.d/project-templates.yaml

@@ -13,7 +13,7 @@
     check:
       jobs:
         - openstack-ansible-functional-debian-buster
-        - openstack-ansible-functional-centos-8
+        - openstack-ansible-functional-centos-8-stream
         - openstack-ansible-functional-ubuntu-focal
     gate:
       jobs:
@@ -31,11 +31,3 @@
       jobs:
         - openstack-ansible-upgrade-ubuntu-focal
 
-- project-template:
-    name: openstack-ansible-role-distro_install-jobs
-    check:
-      jobs:
-        - openstack-ansible-functional-distro_install-centos-8
-    gate:
-      jobs:
-        - openstack-ansible-functional-distro_install-centos-8