Switch tempest jobs to neutron specific ones

In neutron CI queues we were running tempest-slow-py3 and
tempest-ipv6-only jobs which are defined in tempest repository and runs
all tests, e.g related to Swift or Cinder.
This patch defines new jobs: "neutron-tempest-slow-py3" and
"neutron-tempest-ipv6-only" which inherits from the tempest jobs but
disables Cinder and Swift services.
Additionally "neutron-tempest-ipv6-only" job now runs only
"integrated-networking" tox_envlist.

Originally in master branch it was done in patch [1] but due to
completly different structure of zuul config files in stable/ussuri in
newer branches, there is no point to do regular cherry-pick to
stable/train branch from there. So this patch is doing similar change
but it's valid only for stable/train and older branches.

[1] https://review.opendev.org/c/openstack/neutron/+/770630

Conflicts:
    .zuul.yaml

Change-Id: I747aa2c391316210339dc8b8239424ee6b44bb47
(cherry picked from commit 1d64488f5c)

.zuul.yaml

@@ -47,15 +47,7 @@
         - tempest-full-py3:
             timeout: 10800
             irrelevant-files: *tempest-irrelevant-files
-        - tempest-slow-py3:
+        - neutron-tempest-slow-py3
-            irrelevant-files: *tempest-irrelevant-files
-            vars:
-              devstack_localrc:
-                # to avoid https://bugs.launchpad.net/neutron/+bug/1914037
-                # as we couldn't backport the fix to stein release
-                IPV6_PUBLIC_RANGE: 2001:db8:0:10::/64
-                IPV6_PUBLIC_NETWORK_GATEWAY: 2001:db8:0:10::2
-                IPV6_ROUTER_GW_IP: 2001:db8:0:10::1
         - networking-ovn-tempest-dsvm-ovs-release:
             voting: false
             irrelevant-files: *tempest-irrelevant-files
@@ -78,15 +70,7 @@
             timeout: 10800
         - tempest-full-py3:
             timeout: 10800
-        - tempest-slow-py3:
+        - neutron-tempest-slow-py3
-            irrelevant-files: *tempest-irrelevant-files
-            vars:
-              devstack_localrc:
-                # to avoid https://bugs.launchpad.net/neutron/+bug/1914037
-                # as we couldn't backport the fix to stein release
-                IPV6_PUBLIC_RANGE: 2001:db8:0:10::/64
-                IPV6_PUBLIC_NETWORK_GATEWAY: 2001:db8:0:10::2
-                IPV6_ROUTER_GW_IP: 2001:db8:0:10::1
         - grenade-py3:
             irrelevant-files: *tempest-irrelevant-files
     periodic:
@@ -434,3 +418,38 @@
         NEUTRON_DEPLOY_MOD_WSGI: true
     irrelevant-files: *tempest-irrelevant-files
     voting: false
+
+- job:
+    name: neutron-tempest-slow-py3
+    parent: tempest-slow-py3
+    timeout: 10800
+    irrelevant-files: *tempest-irrelevant-files
+    vars:
+      devstack_plugins:
+        neutron: https://opendev.org/openstack/neutron.git
+      devstack_services:
+        br-ex-tcpdump: true
+        br-int-flows: true
+        # Cinder services
+        c-api: false
+        c-bak: false
+        c-sch: false
+        c-vol: false
+        cinder: false
+        # Swift services
+        s-account: false
+        s-container: false
+        s-object: false
+        s-proxy: false
+      devstack_localrc:
+        # to avoid https://bugs.launchpad.net/neutron/+bug/1914037
+        # as we couldn't backport the fix to stein release
+        IPV6_PUBLIC_RANGE: 2001:db8:0:10::/64
+        IPV6_PUBLIC_NETWORK_GATEWAY: 2001:db8:0:10::2
+        IPV6_ROUTER_GW_IP: 2001:db8:0:10::1
+    group-vars:
+      subnode:
+        devstack_services:
+          # Cinder services
+          c-bak: false
+          c-vol: false