feat(eslint): add the ability to add overrides to the extended eslint config

[spaceribs]

This adds an optional parameter to the configuration passed to the ESLint test factory which should allow overrides to be passed into eslint.

Fixes: #1012

[spaceribs]

This may just be an issue in monorepos, and specifically using https://spaceribs.tech/packages/nx-betterer/index.html, it seems like the .eslint file in the sub-project directory has trouble getting parserOptions. Happy to change this upstream in my library if you know what may be incorrect there:

https://github.com/spaceribs/spaceribs/blob/main/packages/nx-betterer/src/executors/betterer/executor.ts