officejs_base: fix document fetch in appstore web section

bt5/officejs_base/SkinTemplateItem/portal_skins/officejs_base/StaticWebSection_getDocumentValue.py

@@ -52,7 +52,7 @@ document_list = context.searchResults(
 
 if len(document_list) == 0:
   # Default returns None
-  document = None
+  return context.WebSection_getDocumentValue(name, **kw)
 else:
   # Try to get the first page on the list
   document = document_list[0]