Update last node version in actions (#489)

Author: kurkle

.github/workflows/npmpublish.yml

@@ -20,7 +20,9 @@ jobs:
     steps:
     - uses: actions/checkout@v2
     - name: Use Node.js
-      uses: actions/setup-node@v1
+    - uses: actions/setup-node@v2
+      with:
+        node-version: 16
     - name: Test
       run: |
         npm ci