allow global return in scripts

.eslintrc.js

@@ -1,6 +1,7 @@
 module.exports = {
 	root: true,
 	extends: '@conduitry',
+	parserOptions: { sourceType: 'script', ecmaFeatures: { globalReturn: true } },
 	env: { node: false },
 	globals: { GM: 'readable', unsafeWindow: 'readable' },
 };