/usr/lib/ruby/vendor_ruby/ is in ruby-roadie-rails 1.1.0-1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/vendor_ruby/roadie-rails.rb
/usr/lib/ruby/vendor_ruby/roadie/
/usr/lib/ruby/vendor_ruby/roadie/rails/
/usr/lib/ruby/vendor_ruby/roadie/rails/inline_on_delivery.rb
/usr/lib/ruby/vendor_ruby/roadie/rails/railtie.rb
/usr/lib/ruby/vendor_ruby/roadie/rails/document_builder.rb
/usr/lib/ruby/vendor_ruby/roadie/rails/mail_inliner.rb
/usr/lib/ruby/vendor_ruby/roadie/rails/version.rb
/usr/lib/ruby/vendor_ruby/roadie/rails/mailer.rb
/usr/lib/ruby/vendor_ruby/roadie/rails/asset_pipeline_provider.rb
/usr/lib/ruby/vendor_ruby/roadie/rails/options.rb
/usr/lib/ruby/vendor_ruby/roadie/rails/automatic.rb
/usr/lib/ruby/vendor_ruby/roadie/rails.rb