counters: Install python dependencies faster

apps/swh-counters/Dockerfile

 # Deeply inspired from the Dockerfile of the swh-storage project
 FROM python:3.10-bullseye
 
+ARG userid=1000
+ARG groupid=1000
+ARG user=swh
+ARG workdir=/opt/${user}
+ARG venv=${workdir}/venv
+ARG configdir=/etc/${user}
+
 # retry command is used by the refresh-history cron job
 # to ensure the rpc service is well up
 RUN apt-get -y update && \
     apt-get -y upgrade && \
     apt-get install -y libcmph-dev librdkafka-dev retry && \
     apt clean && \
-    addgroup --gid 1000 swh && \
-    useradd --gid 1000 --uid 1000 -m -d /opt/swh swh && \
-    mkdir /etc/swh
-
-USER swh
-WORKDIR /opt/swh
+    addgroup --gid ${userid} ${user} && \
+    useradd --gid ${groupid} --uid ${userid} -m -d ${workdir} ${user} && \
+    mkdir ${configdir}
 
-COPY --chown=swh:swh requirements-frozen.txt /opt/swh
+USER ${user}
+RUN python -m venv ${venv}
+WORKDIR ${workdir}
 
-ENV PYTHONPATH=/opt/swh
-ENV PATH=/opt/swh/.local/bin:$PATH
+ENV PYTHONPATH=${venv}
+ENV PATH=${venv}/bin:$PATH
 
-RUN /usr/local/bin/python -m pip install --upgrade pip && \
-    pip install --no-cache-dir -r requirements-frozen.txt
+RUN python -m pip install uv
+COPY --chown=${userid}:${groupid} requirements-frozen.txt ${workdir}
+RUN uv pip sync --no-cache requirements-frozen.txt
 
-COPY --chown=swh:swh entrypoint.sh /opt/swh
-RUN chmod u+x /opt/swh/entrypoint.sh
+COPY --chown=${userid}:${groupid} entrypoint.sh ${workdir}
+RUN chmod u+x ${workdir}/entrypoint.sh
 
-ENV SWH_CONFIG_FILENAME=/etc/swh/config.yml
+ENV SWH_CONFIG_FILENAME=${configdir}/config.yml
 ENV PORT 5011
 EXPOSE $PORT
 ENV THREADS 2