next.js

94c94180 - docs: remove copy mentioning appDir as an experimental feature (#51403)

docs: remove copy mentioning appDir as an experimental feature (#51403) The documentation for `(App or Pages) / Building your Application / Configuring / Eslint` [here](https://nextjs.org/docs/app/building-your-application/configuring/eslint#linting-custom-directories-and-files) is mentioning the appDir as an experimental feature that needs to be enabled. This PR update it's content removing this mention Co-authored-by: JJ Kasper <jj@jjsweb.site>