Add workflow to publish releases to NPM

Author: aboks

.github/workflows/ci.yml

@@ -5,6 +5,8 @@ on:
     branches: [ master ]
   pull_request:
     branches: [ master ]
+  release:
+    types: [ created ]
 
 jobs:
   build:
@@ -25,3 +27,29 @@ jobs:
 
       - name: Run test suite
         run: yarn run test
+
+  publish:
+    needs: build
+    runs-on: ubuntu-latest
+    if: ${{ github.event_name == 'release' }}
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: Setup Node
+        uses: actions/setup-node@v1
+        with:
+          node-version: 12
+          registry-url: https://registry.npmjs.org/
+
+      - name: Install dependencies
+        run: yarn install --frozen-lockfile
+
+      - name: Set new version
+        run: npm version --allow-same-version --no-git-tag-version ${{ github.event.release.tag_name }}
+
+      - name: Publish release
+        run: npm publish
+        env:
+          NODE_AUTH_TOKEN: ${{secrets.NPM_TOKEN}}