Fix DA bug which happens when RegistrarAgent fields are empty

Signed-off-by: Jean Snyman <[email protected]>

keylime/models/registrar/registrar_agent.py

@@ -244,7 +244,7 @@ def commit_changes(self):
 
             # Prepare all record data to be sent to a DA backend according to each field's data type
             for name, field in self.__class__.fields.items():
-                agent_data[name] = field.type.da_dump(self._record_values[name])
+                agent_data[name] = field.type.da_dump(self._record_values.get(name))
 
             # Write dumped data to DA backend as an "agent data" record
             da_manager.backend.record_create(agent_data, None, None, None)