Support dependencies & repositories in .scalafix.conf

[bjaglin]

Since https://github.com/scalacenter/scalafix/pull/1152, scalafix-interfaces allow clients to offload dependency resolution to scalafix using Coursier artifact coordinates & repositories. This should also be available as configuration keys to provide a consistent experience across clients.

rules = [
  "OrganizeImports"
]
dependencies = [
  "com.github.liancheng::organize-imports:0.6.0"
]
respositories = [
  "ivy:https://foo.com/a/b/c/[defaultPattern]"
]

Triggered by https://github.com/scalameta/metals/issues/4070

[tgodzik]

This would be amazing! I am currently working around it by adding a config in the metals user settings, but that is far from perfect.

I would be glad to implement it, but I will most likely not have the time :sweat: