Deprecate use of the Superlinter

[beqqrry-aws]

To remove the SL, first we need to implement linters for all the languages which are currently being covered by the SL. At the time of this writing, those are:

• [ ] Enable standalone linter for PHP (PHPCS)
• [ ] Enable standalone linter for Python (Black)
• [ ] Enable standalone linter for Ruby
• [ ] Enable standalone linter for Kotlin
• [x] #5978

And a final task to remove the SL from our GitHub Actions.

• [ ] Remove Superlinter from GitHub Actions