chore: remove yarn@3 description from example's package.json

Author: nd0ut

example/package.json

@@ -21,6 +21,5 @@
     "eslint": "^8.17.0",
     "eslint-config-next": "^12.1.6",
     "typescript": "^4.7.3"
-  },
-  "packageManager": "yarn@3.2.1"
+  }
 }