Add a job for S3 backup driver

This job tests S3 backup driver with Swift S3 API.

Change-Id: I222c6ee4de01bdaba9ef5e5b5a92889486d6401b
diff --git a/.zuul.yaml b/.zuul.yaml
index 0ad6e1f..68d0178 100644
--- a/.zuul.yaml
+++ b/.zuul.yaml
@@ -11,6 +11,7 @@
         - nova-ceph-multistore:
             voting: false
         - cinder-tempest-plugin-cbak-ceph
+        - cinder-tempest-plugin-cbak-s3
         - cinder-tempest-plugin-basic-wallaby
         - cinder-tempest-plugin-basic-victoria
         - cinder-tempest-plugin-basic-ussuri
@@ -173,6 +174,21 @@
         CINDER_ISCSI_HELPER: tgtadm
 
 - job:
+    name: cinder-tempest-plugin-cbak-s3
+    parent: cinder-tempest-plugin-basic
+    description: |
+      Integration tests that runs with the s3 backup driver with
+      Swift S3 API.
+    vars:
+      devstack_localrc:
+        CINDER_BACKUP_DRIVER: 's3_swift'
+      devstack_services:
+        c-bak: true
+        s3api: true
+        # Workaround: TLS proxy seems to cause S3 signature mismatch.
+        tls-proxy: false
+      tempest_test_regex: '(test_volume_backup|test_volumes_backup|test_snapshot_backup)'
+- job:
     name: cinder-tempest-plugin-basic
     parent: devstack-tempest
     description: |