chmod g=u .env.example for Docker

docker/multi-process/Dockerfile

@@ -23,7 +23,7 @@ ENV OUTDATED_DOCKER_IMAGE_NAMESPACE ${OUTDATED_DOCKER_IMAGE_NAMESPACE}
 
 RUN umask 002 && \
     LC_ALL=en_US.UTF-8 RAILS_ENV=production APP_SECRET_TOKEN=secret DATABASE_ADAPTER=mysql2 ON_HEROKU=true bundle exec rake assets:clean assets:precompile && \
-    chmod g=u /app/Gemfile.lock /app/config/ /app/tmp/
+    chmod g=u /app/.env.example /app/Gemfile.lock /app/config/ /app/tmp/
 
 
 EXPOSE 3000

docker/single-process/Dockerfile

@@ -20,7 +20,7 @@ ENV OUTDATED_DOCKER_IMAGE_NAMESPACE ${OUTDATED_DOCKER_IMAGE_NAMESPACE}
 
 RUN umask 002 && \
     LC_ALL=en_US.UTF-8 RAILS_ENV=production APP_SECRET_TOKEN=secret DATABASE_ADAPTER=mysql2 ON_HEROKU=true bundle exec rake assets:clean assets:precompile && \
-    chmod g=u /app/Gemfile.lock /app/config/ /app/tmp/
+    chmod g=u /app/.env.example /app/Gemfile.lock /app/config/ /app/tmp/
 
 EXPOSE 3000