Update node version references to min v16

Author: seaona

.github/workflows/build-lint-test.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-20.04
     strategy:
       matrix:
-        node-version: [14.x, 16.x]
+        node-version: [16.x, 18.x]
     steps:
       - uses: actions/checkout@v2
       - name: Use Node.js ${{ matrix.node-version }}

.nvmrc

@@ -1 +1 @@
-v12
+v16

README.md

@@ -16,7 +16,7 @@ static-server node_modules/@metamask/test-dapp/dist --port 9011
 
 ### Setup
 
-- Install [Node.js](https://nodejs.org) version 12
+- Install [Node.js](https://nodejs.org) version 16
   - If you are using [nvm](https://github.com/creationix/nvm#installation) (recommended) running `nvm use` will automatically choose the right node version for you.
 - Install [Yarn v1](https://yarnpkg.com/en/docs/install)
 - Run `yarn setup` to install dependencies and run any required post-install scripts

package.json

@@ -3,7 +3,7 @@
   "version": "5.7.0",
   "description": "A simple dapp used in MetaMask e2e tests.",
   "engines": {
-    "node": ">= 12.0.0"
+    "node": ">= 16.0.0"
   },
   "scripts": {
     "setup": "yarn install && yarn allow-scripts",