First working version with devise+rails_admin

Dockerfile

@@ -9,6 +9,7 @@ COPY Gemfile /myapp/Gemfile
 COPY Gemfile.lock /myapp/Gemfile.lock
 RUN bundle install
 COPY . /myapp
+RUN yarn install --check-files
 
 # Add a script to be executed every time the container starts.
 COPY entrypoint.sh /usr/bin/