Merge branch 'debug/container-privileges' into 'master'

Do not run the container as root

See merge request aaron-riedel/shbot!8

Dockerfile

@@ -1,10 +1,14 @@
 FROM python:slim
 
 WORKDIR ./
+ARG PUID=1000
+ENV USER docker
+ENV HOMEDIR "/home/${USER}"
 
-COPY requirements.txt ./
+RUN useradd -u "${PUID}" -m "${USER}"
+USER ${USER}
+WORKDIR ${HOMEDIR}
+COPY . .
 RUN pip install --no-cache-dir -r requirements.txt
 
-COPY . .
-
 CMD [ "python", "./bot.py" ]