Update Dockerfile to streamline the weatherfeeder user creation.

Dockerfile

@@ -64,18 +64,13 @@ WORKDIR /weatherfeeder
 
 # Create an unprivileged user
 RUN useradd \
-      --system \
       --uid 10001 \
-      --create-home \
-      --home-dir /nonexistent \
+      --no-create-home \
       --shell /usr/sbin/nologin \
       weatherfeeder
 
 # Copy the binary
-COPY --from=build /out/weatherfeeder /weatherfeeder/weatherfeeder
-
-# Make sure the user can read config.yml when it’s mounted in
-RUN chown -R weatherfeeder:weatherfeeder /weatherfeeder
+COPY --chown=weatherfeeder:weatherfeeder --from=build /out/weatherfeeder /weatherfeeder/weatherfeeder
 
 USER weatherfeeder