message: Install latest npm in container before express
  The default version of npm in the docker base image fails during npm
  prune with `npm ERR! invalid bin entry for package msgpack-lite`.
  This is a known and fixed bug in npm:
  Ticket:
diff: @@ -2,6 +2,7 @@ FROM node:10 AS builder
  MAINTAINER Tyler Levine <tyler@bitgo.com>
  COPY --chown=node:node . /tmp/bitgo/
  WORKDIR /tmp/bitgo/modules/express
  +RUN npm install npm@latest -g
  USER node
  RUN npm ci && npm prune --production
  FROM node:10-alpine
  