Add Node.js v14 and v16 to CI

Author: rodion-arr

.github/workflows/test.yml

@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        node-version: [8.x, 10.x, 12.x]
+        node-version: [8.x, 10.x, 12.x, 14.x, 16.x]
     steps:
     - uses: actions/checkout@v1
     - name: Use Node.js ${{ matrix.node-version }}