Move to eslint-stylistic (ESLint 9 dropped formatting rules)

[Talent30]

Hi, @sindresorhus, First of all, thank you for maintaining this amazing project.

ESLint is deprecating all the formatting rules, providing us with two alternatives for migration.

1. Remove all the formatting rules in xo. Instead, we recommend users to utilise a code formatter, such as Prettier. This is the recommended approach.
2. Migrate all the formatting rules to ESLint Stylistic.

I am happy to help either way.

[sindresorhus]

I plan to go with 2, but I don't see the point in doing it until ESLint actually hard-deprecates (with runtime warning) or removes the rules. It would be good to let ESLint Stylistic stabilize a bit first.

[Talent30]

Close this for now. Will reopen it again when ESLint 9 releases.

[sindresorhus]

I prefer to keep it open so I won't get more duplicates.

[EdJoPaTo]

Just to add a thought in here: Maybe a noStyle setting (similar to indent or semicolon) would be nice so people can use own formatters easier.

[sindresorhus]

I don't plan any noStyle setting. There's already a prettier setting.