Gemfile in rack-protection-3.0.5 vs Gemfile in rack-protection-3.0.6

@@ -5,10 +5,10 @@
 
 gem 'rake'
 
 rack_version = ENV['rack'].to_s
 rack_version = nil if rack_version.empty? || (rack_version == 'stable')
-rack_version = { github: 'rack/rack' } if rack_version == 'main'
+rack_version = { github: 'rack/rack' } if rack_version == 'head'
 gem 'rack', rack_version
 
 gem 'sinatra', path: '..'
 
 gemspec