Slim down Docker image

This uses a pre-built Python image based on Debian as this should be much faster than building a custom image on top of a full-feature Ubuntu.

Dockerfile

@@ -1,16 +1,7 @@
-FROM ubuntu:20.04
-ENV DEBIAN_FRONTEND noninteractive
+FROM python:3.12-slim
 
-RUN apt-get -qq -y update \
-    && apt-get -qq -y install python3-pip \
-    pkg-config libicu-dev \
-    && apt-get -qq -y autoremove \
-    && apt-get clean \
-    && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
-
-RUN pip3 install --no-binary=:pyicu: pyicu
-
-ENV LANG='en_US.UTF-8'
+RUN apt-get update
+RUN apt-get install make
 
 COPY . /opt/servicelayer
 WORKDIR /opt/servicelayer