feat: upgrade to bobcat (#887)

diff --git a/images/ironic/Earthfile b/images/ironic/Earthfile
index 74b2ed9..5edcd7c 100644
--- a/images/ironic/Earthfile
+++ b/images/ironic/Earthfile
@@ -1,18 +1,21 @@
 VERSION 0.7
 
-image:
-  ARG PROJECT=ironic
-  ARG RELEASE=zed
-  ARG REF=e38735cb95263b0c54f2fd719ff6b714efbddbb3
-  FROM ../openstack-service+image \
-    --PROJECT ${PROJECT} \
-    --RELEASE ${RELEASE} \
-    --PROJECT_REF ${REF} \
+ARG --global PROJECT=ironic
+ARG --global RELEASE=zed
+ARG --global PROJECT_REF=e38735cb95263b0c54f2fd719ff6b714efbddbb3
+
+build:
+  FROM ../openstack-service+builder --RELEASE=${RELEASE}
+  DO ../openstack-service+BUILD_VENV \
+    --PROJECT=${PROJECT} \
+    --PROJECT_REF=${PROJECT_REF} \
     --PIP_PACKAGES "python-dracclient sushy"
-  DO \
-    ../+APT_INSTALL \
+
+image:
+  FROM ../openstack-service+image --RELEASE ${RELEASE} --PROJECT ${PROJECT}
+  COPY +build/venv /var/lib/openstack
+  DO ../+APT_INSTALL \
     --PACKAGES "ethtool ipmitool iproute2 ipxe lshw qemu-utils tftpd-hpa"
-  DO ../+APPLY_PATCHES
   SAVE IMAGE --push \
     ghcr.io/vexxhost/atmosphere/${PROJECT}:${RELEASE} \
-    ghcr.io/vexxhost/atmosphere/${PROJECT}:${REF}
+    ghcr.io/vexxhost/atmosphere/${PROJECT}:${PROJECT_REF}