chore: Remove obsolete runastyle scripts by jcfr · Pull Request #516 · cppcheck-opensource/simplecpp

Removed the runastyle scripts, which are no longer needed given the long-term plan to transition to uncrustify. See #508 (comment)

The astyle instructions were outdated, binaries for version 3.0.1 are no longer available, and using other versions can lead to inconsistent formatting results. Removing these scripts avoids confusion for contributors.