Add job to test with SQLAlchemy master (2.x)

Change-Id: I1ec983ca09cb42bf1ffb701c1ac56f84c4deee8f
Signed-off-by: Stephen Finucane <stephenfin@redhat.com>

.zuul.yaml

@@ -11,6 +11,7 @@
       jobs:
         - cinder-code-coverage:
             voting: false
+        - cinder-sqlalchemy-2x
         - cinder-mypy
         - cinder-tox-bandit-baseline:
             voting: false
@@ -153,6 +154,21 @@
       - ^tools/.*$
       - ^tox.ini$
 
+- job:
+    name: cinder-sqlalchemy-2x
+    parent: openstack-tox-py310
+    description: |
+      Run unit tests with main branch of SQLAlchemy, alembic and oslo.db.
+      Takes advantage of the base tox job's install-siblings feature.
+    # The job only tests the latest and shouldn't be run on the stable branches
+    branches: master
+    required-projects:
+      - name: github.com/sqlalchemy/sqlalchemy
+        override-checkout: main
+      - name: github.com/sqlalchemy/alembic
+        override-checkout: main
+      - name: openstack/oslo.db
+
 - job:
     name: cinder-rally-task
     parent: rally-task-cinder