no-focused-tests doesn't automatically remove `.only` with `--fix` as said by the documentation

[julienw]

Hey folks, and thanks for the great plugin!

I noticed that no-focused-tests doesn't autofix by default, at least when using the flat config, like said in the documentation.

To be fair I prefer that :-) but I was surprised and thought you would be interested.

See this example project: https://github.com/julienw/vitest-eslint-plugin-issue

I tried also to change the plugin's tests, there it looks like that fixable indeed defaults to true when it's not present. That's why I think there might be something related to the flat config migration.

Hope this helps!