zuul: Add a CentOS 8 stream job to integrated-gate-compute

As set out in the governance repo for Xena CentOS 8 stream with py36 is
a supported platform and runtime for the release:

https://governance.openstack.org/tc/reference/runtimes/xena.html

As a result the Nova team want to run CentOS 8 stream based jobs within
the integrated-gate-compute template.

An additional tempest-full-py3-centos-8-stream job is added to Tempest's
check and gate queues to ensure coverage here.

Both jobs are given additional swap to workaround bug #1949606, a
behaviour change in QEMU >= 5.0.0 when using [libvirt]virt_type=qemu
that causes additional memory to be consumed by each running instance.

This workaround of additional swap will be removed in the future once
Nova is able to workaround this itself through a new libvirt domain
configurable.

Change-Id: I4b074dca58960b2622dde15ad7d9a91b3ba0c096

zuul.d/integrated-gate.yaml

@@ -128,6 +128,20 @@
         s-proxy: false
         c-bak: false
 
+- job:
+    name: tempest-integrated-compute-centos-8-stream
+    parent: tempest-integrated-compute
+    nodeset: devstack-single-node-centos-8-stream
+    description: |
+      This job runs integration tests for compute. This is
+      subset of 'tempest-full-py3' job and run Nova, Neutron, Cinder (except backup tests)
+      and Glance related tests. This is meant to be run on Nova gate only.
+      This version of the job also uses CentOS 8 stream.
+    vars:
+      # Required until bug/1949606 is resolved when using libvirt and QEMU
+      # >=5.0.0 with a [libvirt]virt_type of qemu (TCG).
+      configure_swap_size: 4096
+
 - job:
     name: tempest-integrated-placement
     parent: devstack-tempest
@@ -318,9 +332,11 @@
     check:
       jobs:
         - tempest-integrated-compute
+        - tempest-integrated-compute-centos-8-stream
     gate:
       jobs:
         - tempest-integrated-compute
+        - tempest-integrated-compute-centos-8-stream
 
 - project-template:
     name: integrated-gate-placement

zuul.d/project.yaml

@@ -118,6 +118,8 @@
             irrelevant-files: *tempest-irrelevant-files
         - openstack-tox-bashate:
             irrelevant-files: *tempest-irrelevant-files-2
+        - tempest-full-py3-centos-8-stream:
+            irrelevant-files: *tempest-irrelevant-files
     gate:
       jobs:
         - tempest-slow-py3:
@@ -126,6 +128,8 @@
             irrelevant-files: *tempest-irrelevant-files
         - tempest-full-py3:
             irrelevant-files: *tempest-irrelevant-files
+        - tempest-full-py3-centos-8-stream:
+            irrelevant-files: *tempest-irrelevant-files
         - grenade:
             irrelevant-files: *tempest-irrelevant-files
         - tempest-ipv6-only:

zuul.d/tempest-specific.yaml

@@ -77,6 +77,18 @@
       on openSUSE Leap 15.x
     voting: false
 
+- job:
+    name: tempest-full-py3-centos-8-stream
+    parent: tempest-full-py3
+    nodeset: devstack-single-node-centos-8-stream
+    description: |
+      Base integration test with Neutron networking and py36 running
+      on CentOS 8 stream
+    vars:
+      # Required until bug/1949606 is resolved when using libvirt and QEMU
+      # >=5.0.0 with a [libvirt]virt_type of qemu (TCG).
+      configure_swap_size: 4096
+
 - job:
     name: tempest-tox-plugin-sanity-check
     parent: tox