add npm-publish workflow

.github/workflows/npm-publish.yml

@@ -0,0 +1,22 @@
+---
+name: Node.js Package
+
+on:
+  push:
+    tags:
+      - 'v*'
+
+jobs:
+  publish-npm:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-node@v2
+        with:
+          node-version: 'lts/*'
+          registry-url: https://registry.npmjs.org/
+      - run: npm ci
+      - run: npm test
+      - run: npm publish
+        env:
+          NODE_AUTH_TOKEN: ${{secrets.npm_token}}