Remove detailed_message shim in Rails::Command

Now that we require Ruby 3.2, we can assume it's defined.

Author: byroot

railties/lib/rails/command.rb

@@ -23,12 +23,6 @@ def initialize(message, name, alternatives)
         super(message)
       end
 
-      if !Exception.method_defined?(:detailed_message) # Ruby 3.2+
-        def detailed_message(...)
-          message
-        end
-      end
-
       if defined?(DidYouMean::Correctable) && defined?(DidYouMean::SpellChecker)
         include DidYouMean::Correctable