fix: pin base image digests for stable/2023.2

Signed-off-by: Claude <noreply@anthropic.com>

Author: mnaser

Dockerfile

@@ -2,7 +2,7 @@
 # SPDX-License-Identifier: GPL-3.0-or-later
 # Atmosphere-Rebuild-Time: 2024-06-26T17:38:39Z
 
-FROM ghcr.io/vexxhost/openstack-venv-builder:2023.2 AS build
+FROM ghcr.io/vexxhost/openstack-venv-builder:2023.2@sha256:5d8ae218f2f9691db6a33aa3b45ee82c49a2815d8e54a62c7cf857d4b4853f7c AS build
 RUN <<EOF bash -xe
 uv pip install \
     --constraint /upper-constraints.txt \
@@ -20,7 +20,7 @@ uv pip install \
         python-swiftclient
 EOF
 
-FROM ghcr.io/vexxhost/python-base:2023.2
+FROM ghcr.io/vexxhost/python-base:2023.2@sha256:bddcab6ad70beb092dc9c67d799f8840fecd6bb1dcb6e7a07c62f8d46b817aa9
 COPY --from=build --link /var/lib/openstack /var/lib/openstack
 
 # NOTE(mnaser): The Magnum client relies on the SHELL environment variable