added copy step to build

Author: Jay Nanduri

.github/workflows/npm-publish.yml

@@ -17,6 +17,8 @@ jobs:
           node-version: 12
           registry-url: https://npm.pkg.github.com/
       - run: npm ci
+      - name: npm build
+        run: npm run build
       - name: Set up NPM authentication
         run: echo "//npm.pkg.github.com/:_authToken=${{ secrets.GITHUB_TOKEN }}" >> ~/.npmrc
       - run: npm publish --access public