chore: check formatting on CI

Author: ugogo

.github/workflows/lint.yml

@@ -21,3 +21,6 @@ jobs:
 
       - name: Lint
         run: npm run lint
+
+      - name: Check formatting
+        run: npm run format:check

package.json

@@ -37,7 +37,8 @@
     "test:watch": "react-scripts test --env=jsdom",
     "release": "npm run test && npm run prepare && dotenv release-it",
     "lint": "eslint . --ext .js,.ts,.tsx",
-    "format": "prettier --write {src,playground}"
+    "format": "prettier --write {src,playground}",
+    "format:check": "prettier --check {src,playground}/**/*.{ts,tsx}"
   },
   "peerDependencies": {
     "react": ">=16.0.0",