use alpine to lower the image size

Dockerfile.contactform

@@ -1,5 +1,5 @@
 ### BUILDER
-FROM python:3.12-bookworm as builder
+FROM python:3.12-alpine as builder
 
 RUN pip install poetry==1.8.3
 
@@ -16,13 +16,14 @@ RUN touch README.md
 RUN --mount=type=cache,target=$POETRY_CACHE_DIR poetry install --no-root
 
 ### RUNTIME
-FROM python:3.12-bookworm as runtime
+FROM python:3.12-alpine as runtime
 
 WORKDIR /app
 
-RUN apt-get update && \
-    apt-get install -y nginx chromium dbus && \
-    rm -rf /var/lib/apt/lists/*
+RUN apk upgrade --no-cache --available \
+    && apk add --no-cache \
+    chromium-swiftshader \
+    nginx
 
 ENV VIRTUAL_ENV=/app/.venv \
     PATH="/app/.venv/bin:$PATH" \
@@ -35,9 +36,8 @@ COPY contactform ./contactform
 COPY nginx.conf /etc/nginx/nginx.conf
 
 RUN set -x && \
-    useradd -ms /bin/bash contactform && \
+    adduser -D contactform && \
     mkdir -p /opt/data && \
-    ls -Alh /opt/data && \
     chown -R contactform:root /app /opt/data /var/log/nginx /var/lib/nginx && \
     chmod -R g=u /app /opt/data /var/log/nginx /var/lib/nginx