Run configlet fmt on all tracks

[kytrinyx]

In the coming months we will be submitting scripted pull requests to the tracks with various nextercism-related changes to the config files.

By normalizing the config files, we will reduce the amount of noise in those PRs.
See documentation about configlet here: https://github.com/exercism/docs/blob/master/language-tracks/configuration/configlet.md