configure npm publish via CI

Author: endel

.github/workflows/ci.yml

@@ -1,4 +1,4 @@
-name: CI
+name: Test and Publish
 
 on:
   pull_request:
@@ -30,3 +30,22 @@ jobs:
 
       - name: Test
         run: npm test -- --run
+
+      - id: check
+        uses: EndBug/version-check@v2
+        with:
+          file-name: package.json
+          diff-search: true
+
+      - name: Publish package on NPM 📦
+        if: steps.check.outputs.changed == 'true'
+        run: npm publish
+        env:
+          NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}
+
+      - name: Release
+        if: steps.check.outputs.changed == 'true'
+        uses: softprops/action-gh-release@v1
+        with:
+          tag_name: ${{ steps.check.outputs.version }}
+          prerelease: false