Added Rubocop harness to enforce Ruby code style
diff --git a/lib/rb/Gemfile b/lib/rb/Gemfile
index 83ff867..f3da0a3 100644
--- a/lib/rb/Gemfile
+++ b/lib/rb/Gemfile
@@ -5,3 +5,5 @@
 # Only required for tests with Rack 2.x on Ruby 4.0+
 gem 'cgi'
 gem 'ostruct'
+
+eval_gemfile File.expand_path("Gemfile.linters", __dir__)