Automate Publish to NPM (#4)

- initial publish workflow

Author: mwarman

.github/workflows/publish.yml

@@ -0,0 +1,27 @@
+name: Publish
+
+on:
+  release:
+    types:
+      - published
+  workflow_dispatch:
+
+jobs:
+  build:
+    name: Build
+
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
+
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-node@v3
+        with:
+          node-version-file: '.nvmrc'
+          cache: 'npm'
+          registry-url: 'https://registry.npmjs.org'
+      - run: npm ci
+      - run: num run build
+      - run: npm publish
+        env:
+          NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}