remove kcc_config files from version control

[charala1]

This was added to prevent differences in error messages depending on whether that file was produced or not. It might not be needed anymore because I think we're chopping that line now anyway, but please verify locally -- these tests are run on rv-match, not in the c-sem pr job.

Originally posted by @chathhorn in https://github.com/kframework/c-semantics/pull/473#issuecomment-502783315