What's the use case for this utility now that plugins have been moved to the ESLint-compatible config?

• direct XO cli users don't need it
• ESLint users should use eslint-config-xo
• XO cli users that want IDE integration should not be able to further customize XO inline just for the IDE

Suggested changes

Since only the last use case makes sense (AFAIK), customization should be removed from this helper:

• Remove function parameter
• Change usage to export {default} from 'xo/eslint-adapter'

The adapter should then just read XO's config from its native config locations (xo.config.ts, package.json)