CI: test against node v21

Author: ivandotv

.github/workflows/CI.yml

@@ -13,7 +13,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        node: ['12', '14', '16']
+        node: ['21']
     steps:
       - name: Checkout
         uses: actions/checkout@v2
@@ -51,7 +51,7 @@ jobs:
 
       - name: Generate Code Coverage
         # only when running in node v16
-        if: matrix.node == 16
+        if: matrix.node == 21
         uses: codecov/codecov-action@v2
         with:
           token: ${{ secrets.CODECOV_TOKEN }}