/usr/lib/ruby/vendor_ruby/ is in ruby-grit 2.5.0-4.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/vendor_ruby/grit/
/usr/lib/ruby/vendor_ruby/grit/actor.rb
/usr/lib/ruby/vendor_ruby/grit/blame.rb
/usr/lib/ruby/vendor_ruby/grit/blob.rb
/usr/lib/ruby/vendor_ruby/grit/commit.rb
/usr/lib/ruby/vendor_ruby/grit/commit_stats.rb
/usr/lib/ruby/vendor_ruby/grit/config.rb
/usr/lib/ruby/vendor_ruby/grit/diff.rb
/usr/lib/ruby/vendor_ruby/grit/errors.rb
/usr/lib/ruby/vendor_ruby/grit/git-ruby/
/usr/lib/ruby/vendor_ruby/grit/git-ruby/commit_db.rb
/usr/lib/ruby/vendor_ruby/grit/git-ruby/git_object.rb
/usr/lib/ruby/vendor_ruby/grit/git-ruby/internal/
/usr/lib/ruby/vendor_ruby/grit/git-ruby/internal/file_window.rb
/usr/lib/ruby/vendor_ruby/grit/git-ruby/internal/loose.rb
/usr/lib/ruby/vendor_ruby/grit/git-ruby/internal/pack.rb
/usr/lib/ruby/vendor_ruby/grit/git-ruby/internal/raw_object.rb
/usr/lib/ruby/vendor_ruby/grit/git-ruby/repository.rb
/usr/lib/ruby/vendor_ruby/grit/git-ruby.rb
/usr/lib/ruby/vendor_ruby/grit/git.rb
/usr/lib/ruby/vendor_ruby/grit/index.rb
/usr/lib/ruby/vendor_ruby/grit/lazy.rb
/usr/lib/ruby/vendor_ruby/grit/merge.rb
/usr/lib/ruby/vendor_ruby/grit/ref.rb
/usr/lib/ruby/vendor_ruby/grit/repo.rb
/usr/lib/ruby/vendor_ruby/grit/ruby1.9.rb
/usr/lib/ruby/vendor_ruby/grit/status.rb
/usr/lib/ruby/vendor_ruby/grit/submodule.rb
/usr/lib/ruby/vendor_ruby/grit/tag.rb
/usr/lib/ruby/vendor_ruby/grit/tree.rb
/usr/lib/ruby/vendor_ruby/grit.rb