Only use Node 16.x in CI

.github/workflows/ci.yml

@@ -1,6 +1,3 @@
-# This workflow will do a clean installation of node dependencies, cache/restore them, build the source code and run tests across different versions of node
-# For more information see: https://help.github.com/actions/language-and-framework-guides/using-nodejs-with-github-actions
-
 name: CI
 
 on:
@@ -8,20 +5,13 @@ on:
 
 jobs:
   build:
-
     runs-on: ubuntu-latest
-
-    strategy:
-      matrix:
-        node-version: [12.x, 14.x, 16.x]
-        # See supported Node.js release schedule at https://nodejs.org/en/about/releases/
-
     steps:
     - uses: actions/checkout@v3
-    - name: Use Node.js ${{ matrix.node-version }}
+    - name: Use Node.js 16.x
       uses: actions/setup-node@v3
       with:
-        node-version: ${{ matrix.node-version }}
+        node-version: 16.x
         cache: 'npm'
     - run: npm ci
     - run: npm run all