Explode directories into individual files

Without this the directory is passed to require when
definition file path is not used. Ruby cannot require
directories so it explodes.

Author: kennyadsl

lib/solidus_dev_support/testing_support/factories.rb

@@ -55,6 +55,8 @@ def self.load_for(*engines)
                 is only used to load ./factories content.
               WARN
 
+              engine.root.glob('lib/*/testing_support/factories/**/*_factory.rb')
+            elsif factories_file_or_folder.first.directory?
               engine.root.glob('lib/*/testing_support/factories/**/*_factory.rb')
             else
               factories_file_or_folder