Run Rubocop with lint-staged on commit (#24644)

package.json

@@ -212,6 +212,7 @@
   },
   "lint-staged": {
     "*": "prettier --ignore-unknown --write",
+    "Capfile|Gemfile|*.{rb,ruby,ru,rake}": "bundle exec rubocop -a",
     "*.{js,jsx,ts,tsx}": "eslint --fix",
     "*.{css,scss}": "stylelint --fix"
   }