Remove expected status on Rails 7.1

Author: JonRowe

example_app_generator/spec/verify_mailer_preview_path_spec.rb

@@ -41,7 +41,7 @@ def have_no_preview(opts = {})
         else
           "#{::Rails.root}/test/mailers/previews"
         end
-      have_attributes(io: expected_io, exit_status: 0)
+      have_attributes(io: expected_io)
     end
   else
     let(:expected_custom_path) { '/custom/path' }