Change the default value of dependency to an empty tuple.

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@4369 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5/PropertySheet/BusinessTemplate.py

@@ -145,7 +145,7 @@ class BusinessTemplate:
       'description' : 'a list of template names required by this template',
       'type'        : 'lines',
       'mode'        : 'w',
-      'default'     : '' },
+      'default'     : () },
     { 'id'          : 'template_format_version',
       'description' : 'Business Template format version',
       'type'        : 'int',