Use Node v12 for UI development

.circleci/config.yml

@@ -703,7 +703,7 @@ jobs:
     docker:
     - environment:
         JOBS: 2
-      image: docker.mirror.hashicorp.services/circleci/node:10-browsers
+      image: docker.mirror.hashicorp.services/circleci/node:12-browsers
     steps:
     - checkout
     - restore_cache:

.circleci/config/jobs/test-ui.yml

@@ -1,5 +1,5 @@
 docker:
-  - image: docker.mirror.hashicorp.services/circleci/node:10-browsers
+  - image: docker.mirror.hashicorp.services/circleci/node:12-browsers
     environment:
       # See https://git.io/vdao3 for details.
       JOBS: 2

scripts/vagrant-linux-unpriv-ui.sh

@@ -1,7 +1,7 @@
 #!/usr/bin/env bash
 
 # Install NVM for simple node.js version management
-curl -sSL --fail -o- https://raw.githubusercontent.com/creationix/nvm/v0.33.11/install.sh | bash
+curl -sSL --fail -o- https://raw.githubusercontent.com/creationix/nvm/v0.36.0/install.sh | bash
 
 # This enables NVM without a logout/login
 export NVM_DIR="/home/vagrant/.nvm"
@@ -9,9 +9,9 @@ export NVM_DIR="/home/vagrant/.nvm"
 [ -s "$NVM_DIR/nvm.sh" ] && . "$NVM_DIR/nvm.sh"  # This loads nvm
 
 # Install Node, Ember CLI, and Phantom for UI development
-nvm install 10.15.3
-nvm alias default 10.15.3
+nvm install 12
+nvm alias default 12
 npm install -g ember-cli
 
 # Install Yarn for front-end dependency management
-curl -o- -L https://yarnpkg.com/install.sh | bash -s -- --version 1.15.2
+curl -o- -L https://yarnpkg.com/install.sh | bash -s -- --version 1.22.5

ui/.nvmrc

@@ -1 +1 @@
-10
+12