Test: Add Node.js v21 and update GitHub Actions (#67)

Author: cclauss

.github/workflows/test.yml

@@ -5,14 +5,14 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, macos-latest, windows-latest]
-        node: [16, 18, 20]
+        node: [18, 20, 22, latest]  # https://nodejs.org/en/about/previous-releases
     runs-on: ${{ matrix.os }}
     name: ${{ matrix.os }} / Node ${{ matrix.node }}
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
       - name: Use node ${{ matrix.node }}
-        uses: actions/setup-node@v3
+        uses: actions/setup-node@v4
         with:
           node-version: ${{ matrix.node }}
       - name: Install