feat: upgrade to bobcat (#887)

diff --git a/images/senlin/Earthfile b/images/senlin/Earthfile
index 60da266..7e67788 100644
--- a/images/senlin/Earthfile
+++ b/images/senlin/Earthfile
@@ -1,14 +1,18 @@
 VERSION 0.7
 
+ARG --global PROJECT=senlin
+ARG --global RELEASE=2023.2
+ARG --global PROJECT_REF=5382259276d6be6807634c58c7b69b03b57ad6f5
+
+build:
+  FROM ../openstack-service+builder --RELEASE=${RELEASE}
+  DO ../openstack-service+BUILD_VENV \
+    --PROJECT=${PROJECT} \
+    --PROJECT_REF=${PROJECT_REF}
+
 image:
-  ARG PROJECT=senlin
-  ARG RELEASE=zed
-  ARG REF=b6ef17b0f787fb7a0609ba36dc13097882a6a3ff
-  FROM ../openstack-service+image \
-    --PROJECT ${PROJECT} \
-    --RELEASE ${RELEASE} \
-    --PROJECT_REF ${REF}
-  DO ../+APPLY_PATCHES
+  FROM ../openstack-service+image --RELEASE ${RELEASE} --PROJECT ${PROJECT}
+  COPY +build/venv /var/lib/openstack
   SAVE IMAGE --push \
     ghcr.io/vexxhost/atmosphere/${PROJECT}:${RELEASE} \
-    ghcr.io/vexxhost/atmosphere/${PROJECT}:${REF}
+    ghcr.io/vexxhost/atmosphere/${PROJECT}:${PROJECT_REF}