Temporarily add transformer fix

bullet_train-super_scaffolding/lib/scaffolding/transformer.rb

@@ -841,14 +841,22 @@ def valid_#{collection_name}
           field_options[:color_picker_options] = "t('#{child.pluralize.underscore}.fields.#{name}.options')"
         end
 
+        # When rendering a super_select element we need to use `html_options: {multiple: true}`,
+        # but all other fields simply use `multiple: true` to work.
+        if is_multiple
+          if type == "super_select"
+            field_options[:multiple] = "true"
+          else
+            field_attributes[:multiple] = "true"
+          end
+        end
+
         valid_values = if is_id
           "valid_#{name_without_id.pluralize}"
         elsif is_ids
           "valid_#{collection_name}"
         end
 
-        field_options[:multiple] = "true" if is_multiple
-
         # https://stackoverflow.com/questions/21582464/is-there-a-ruby-hashto-s-equivalent-for-the-new-hash-syntax
         if field_options.any? || options.any?
           field_options_key = if ["buttons", "super_select", "options"].include?(type)