docker(minor): give user a fixed UID, use --chown flag for docker COPY

Dockerfile

@@ -1,9 +1,8 @@
 FROM docker.beryju.org/passbook/base:latest
 
-COPY ./passbook/ /app/passbook
+COPY --chown=passbook:passbook ./passbook/ /app/passbook
 COPY ./manage.py /app/
 COPY ./docker/uwsgi.ini /app/
-RUN chown -R passbook: /app
 
 WORKDIR /app/
 

base.Dockerfile

@@ -15,5 +15,4 @@ RUN apt-get update && \
 RUN pipenv lock -r > requirements.txt && \
     pipenv --rm && \
     pip install -r requirements.txt  --no-cache-dir && \
-    adduser --system --no-create-home passbook && \
-    chown -R passbook /app
+    adduser --system --no-create-home --uid 1000 --group --home /app passbook