require ruby 3.2+ for Data object access

Author: violet-graves

luhn.gemspec

@@ -1,6 +1,7 @@
 # encoding: UTF-8
 require File.expand_path('../lib/luhn/version', __FILE__)
 
+
 Gem::Specification.new do |s|
   s.name         = 'luhn'
   s.homepage     = 'http://github.com/joeljunstrom/ruby_luhn'
@@ -12,5 +13,7 @@ Gem::Specification.new do |s|
   s.platform     = Gem::Platform::RUBY
   s.files        = Dir.glob("{lib,spec}/**/*") + %w[LICENSE README.rdoc]
 
+  s.required_ruby_version = '>= 3.2'
+
   s.add_development_dependency 'minitest', '~> 2.6.0'
-end
+end