Use eslint path to choose where to load eslint's config library

[timruffles]

eslint uses a pretty simple algorithm to work out where the 'project' lives - and node_modules for plugins/configs are loaded relative to - __dirname + '/../../..'.

This means using prettier-eslint-cli's own version of eslint means plugins/configs cannot be loaded. Using the eslint install from eslintPath passed in is more consistent, and provides a way to use config/plugins from node_modules.

Fixes #127

[zimme]

Let's do another PR is using a different require method outlined in #144 and see if these changes are needed as well.

[fantapop]

I very much need this. Having to add this commit manually each time I need to update prettier-eslint-cli.

[timruffles]

@zimme worth looping round to check/include this?

[chrisbobbe]

FYI, using ConfigFile.load isn't viable with ESLint 6 or later; see #303. This may result in confusion if someone has ESLint 6 or later installed at their project level, especially since prettier-eslint-cli doesn't pin to a valid version range for ESLint in its peer dependencies (it doesn't do that for prettier-eslint either).

[kylemh]

Hey @timruffles I know it's been a hot minute, but I'm spending a few hours a weekend working on this repo and prettier-eslint. Feel free to resolve the conflicts, and I'll work on getting this in!

Looking at #144 as well!

[github-actions]

Stale pull request

[idahogurl]

I believe this was already fixed in #431
Plus this PR is no longer relevant as the ESLint API has radically changed.

[JounQin]

Close due to inactive, please feel free to create a new issue with minimal but runnable reproduction. Thanks!