drop ruby 3.1 support (#191)

Author: modosc

.rubocop.yml

@@ -7,7 +7,7 @@ require:
 
 AllCops:
   NewCops: enable
-  TargetRubyVersion: 3.1
+  TargetRubyVersion: 3.2
   SuggestExtensions: false
 
 Style/Documentation:

cloudflare-rails.gemspec

@@ -34,7 +34,6 @@ Gem::Specification.new do |spec|
   spec.add_dependency 'railties', '>= 7.1.0', '< 8.1.0'
   spec.add_dependency 'zeitwerk', '>= 2.5.0'
 
-  # rails 7.2 lists this as the minimum
-  spec.required_ruby_version = '>= 3.1.0'
+  spec.required_ruby_version = '>= 3.2.0'
   spec.metadata['rubygems_mfa_required'] = 'true'
 end