Speed up deploy by faster docker build

Dockerfile

@@ -35,6 +35,17 @@ COPY --from=js-static $APP_DIR/bundles ./bundles
 
 RUN uv run --locked -- ./manage.py collectstatic
 
+FROM python:3.12 AS vault-lambda-extension
+
+WORKDIR /vault
+
+# https://developer.hashicorp.com/vault/docs/platform/aws/lambda-extension
+ADD --checksum=sha256:69b95ca2f99196868077fa5d360db24aaed16fdf6038e72273163aa4cc372b0b \ 
+    https://releases.hashicorp.com/vault-lambda-extension/0.10.3/vault-lambda-extension_0.10.3_linux_amd64.zip \
+    /vault.zip
+
+RUN python -m zipfile -e /vault.zip /vault
+
 FROM amazon/aws-lambda-python:3.12
 
 COPY --from=ghcr.io/astral-sh/uv:0.2.37 /uv /bin/uv
@@ -43,27 +54,17 @@ ARG FUNCTION_DIR="/var/task/"
 
 COPY pyproject.toml uv.lock $FUNCTION_DIR
 
-# Setup Python environment
-RUN dnf install -y unzip \
-    # silent, show errors and location (aka follow redirect)
-    && curl -sSL --output vault-lambda-extension.zip \
-        https://releases.hashicorp.com/vault-lambda-extension/0.10.3/vault-lambda-extension_0.10.3_linux_amd64.zip \
-    && unzip vault-lambda-extension.zip -d /opt \
-    && dnf remove -y unzip \
-    && dnf clean all \
-    && rm vault-lambda-extension.zip \
-    && rm -rf /var/cache/dnf
-
 # FIXME: once uv supports using uv.lock to install into system python this should actually use the lockfile
 RUN uv pip install -r pyproject.toml --extra prod --verify-hashes --no-cache --system --compile-bytecode && rm /bin/uv
 
 COPY ./ $FUNCTION_DIR
 
 RUN ZAPPA_HANDLER_PATH=$(python -c "from zappa import handler; print (handler.__file__)") \
-    && echo $ZAPPA_HANDLER_PATH \
-    && cp $ZAPPA_HANDLER_PATH $FUNCTION_DIR
+&& echo $ZAPPA_HANDLER_PATH \
+&& cp $ZAPPA_HANDLER_PATH $FUNCTION_DIR
 
 COPY --from=static-files /srv/app/webpack-stats.json ./
+COPY --from=vault-lambda-extension /vault/extensions/vault-lambda-extension /opt/extensions/vault-lambda-extension
 ARG VERSION
 # https://docs.sentry.io/platforms/python/guides/logging/configuration/releases/#setting-a-release
 ENV SENTRY_VERSION=${VERSION}