Upgrade web docker build base image to node:10
## bundle web assets
-FROM node:6.7.0 as webpack-bundle
-RUN curl -o- -L https://yarnpkg.com/install.sh | bash
+FROM node:10 as webpack-bundle
+RUN curl -o- -L https://yarnpkg.com/install.sh | bash -s -- --version 1.7.0
ENV HOME /root
ENV PATH $HOME/.yarn/bin:$PATH
