Reset tmp dir in docker build, fix permissions

Author: mtnstar

Diff for: Dockerfile

@@ -34,7 +34,7 @@ RUN    bundle config set --local deployment 'true' \
     && bundle install \
     && bundle clean
 
-RUN rm -rf vendor/cache/ .git
+RUN rm -rf vendor/cache/ .git tmp
 
 # build frontend
 RUN yarn global add [email protected]
@@ -46,6 +46,8 @@ RUN apt-get autoremove -y
 
 RUN adduser --disabled-password --uid 1001 --gid 0 --gecos "" app
 
+RUN mkdir /app-src/tmp && chown -R 1001 /app-src/tmp
+
 USER 1001
 
 # make sure unique secret key is set by operator