dnsmasq: switch to Debian, pin versions

Turns out Alpine project does not really follow semver and removes any
outdated packages from their repositories as soon as the new versions
are released. This results in a non-reproducible builds.

See https://gitlab.alpinelinux.org/alpine/abuild/-/issues/9996 for more
details.

This commit switches the base image to a slimmed down version of Debian,
which allows us to use more stable package versioning at the cost of
increasing image size from ~75MB to ~120MB.

Closes PUC-241.

argo-workflows/generic/containers/Dockerfile.python312_alpine

@@ -1,3 +1,4 @@
+
 FROM python:3.12.2-alpine3.19 as builder
 
 LABEL org.opencontainers.image.title="Python 3.12 image base image"

containers/Dockerfile.dnsmasq

@@ -1,7 +1,10 @@
 # syntax=docker/dockerfile:1
-FROM alpine:3.19.1
+FROM debian:bookworm-20240408-slim
 
-RUN apk add --update --no-cache dnsmasq=2.90-r2 python3=3.11.8-r0 py3-pip=23.3.1-r0 py3-jinja2=3.1.2-r3
+RUN apt-get update && \
+    apt-get -y install --no-install-recommends dnsmasq=2.89-1 python3-jinja2=3.1.2-1 && \
+    apt-get clean && \
+    rm -rf /var/lib/apt/lists/*
 
 COPY common/helpers.sh /helpers.sh
 COPY dnsmasq/entry-point.sh /entry-point.sh