check the existence of workflow_history to avoid possible AttributeError.

product/ERP5Configurator/Document/BusinessConfiguration.py

@@ -97,8 +97,10 @@ class BusinessConfiguration(Item):
   def initializeWorkflow(self):
     """ Initialize Related Workflow"""
     workflow = self.getResourceValue()
+    workflow_history = getattr(self, 'workflow_history', None)
     if workflow is not None and \
-      (self.getResource() not in self.workflow_history):
+      workflow_history is not None and \
+      (self.getResource() not in workflow_history):
       if len(self.objectValues("ERP5 Configuration Save")) > 0:
         raise ValueError("Business Configuration Cannot be initialized, \
                           it contains one or more Configurator Save")