Add octavia-grenade-slurp CI job

Added new job according to [1] to test the new SLURP (a.k.a tick-tock)
upgrade strategy.

[1] https://lists.openstack.org/pipermail/openstack-discuss/2022-September/030654.html

Change-Id: Ia8c35071f54e6988d9b2ff682a529bd477b93b74

Author: weinimo

zuul.d/jobs.yaml

@@ -32,13 +32,13 @@
     name: octavia-grenade
     parent: grenade
     nodeset: octavia-single-node-ubuntu-focal
-    required-projects:
+    required-projects: &o-grenade-required-projects
       - opendev.org/openstack/grenade
       - opendev.org/openstack/octavia
       - opendev.org/openstack/octavia-lib
       - opendev.org/openstack/octavia-tempest-plugin
       - opendev.org/openstack/python-octaviaclient
-    vars:
+    vars: &o-grenade-vars
       grenade_devstack_localrc:
         shared:
           DIB_LOCAL_ELEMENTS: openstack-ci-mirrors
@@ -78,10 +78,14 @@
         '/var/log/octavia-amphora.log': 'logs'
 
 - job:
-    name: octavia-grenade-ffu
-    parent: octavia-grenade
-    vars:
-      grenade_from_branch: stable/stein
+    name: octavia-grenade-skip-level
+    description: |
+      Grenade job that skips a release, validating that deployers can skip
+      specific releases as prescribed by our process.
+    parent: grenade-skip-level
+    nodeset: octavia-single-node-ubuntu-focal
+    required-projects: *o-grenade-required-projects
+    vars: *o-grenade-vars
 
 - job:
     name: octavia-v2-dsvm-scenario-amphora-v2

zuul.d/projects.yaml

@@ -56,7 +56,7 @@
         - octavia-v2-dsvm-tls-barbican:
             irrelevant-files: *irrelevant-files
         - octavia-grenade:
-            irrelevant-files:
+            irrelevant-files: &grenade-irrelevant-files
               - ^.*\.rst$
               - ^api-ref/.*$
               - ^doc/.*$
@@ -66,6 +66,8 @@
               - ^tools/.*$
               - ^(test-|)requirements.txt$
               - ^tox.ini$
+        - octavia-grenade-skip-level:
+            irrelevant-files: *grenade-irrelevant-files
         - octavia-v2-dsvm-tls-barbican-fips:
             irrelevant-files: *irrelevant-files
             voting: false
@@ -114,14 +116,14 @@
         - octavia-v2-dsvm-scenario
         - octavia-v2-dsvm-tls-barbican
         - octavia-grenade
+        - octavia-grenade-skip-level
     periodic:
       jobs:
         - publish-openstack-octavia-amphora-image-focal:
             branches: ^(?!stable/.*).*$
         - publish-openstack-octavia-amphora-image-centos-9-stream:
             branches: ^(?!stable/.*).*$
         - octavia-amphora-image-build
-        - octavia-grenade-ffu
 # Putting octavia-v2-dsvm-scenario-fips in periodic as centos 8 is too slow
         - octavia-v2-dsvm-scenario-fips:
             voting: false