Update jest (#429)

* Update jest

* Switch to node:12

Author: danecreekphotography

.devcontainer/Dockerfile

@@ -2,7 +2,7 @@
 # This is most important for git: if git is installed via postCreateCommand it actually isn't there in
 # time for first container creation. VSCode will attempt to copy the .gitconfig file and fail
 # because git isn't installed
-FROM node:slim
+FROM node:12
 
 ARG NPM_GLOBAL=/usr/local/share/npm-global
 ARG USERNAME=node

Dockerfile

@@ -1,5 +1,5 @@
 # This temporary image is used to produce the build.
-FROM node:slim as build
+FROM node:12 as build
 RUN mkdir -p /home/node/app/fonts && chown -R node:node /home/node/app
 
 WORKDIR /home/node/app