dispatch: write message to file properly in py3

dr_botzo/dispatch/views.py

@@ -90,8 +90,7 @@ class DispatchMessage(generics.GenericAPIView):
                     filename = os.path.abspath(action.destination)
                     log.debug("sending '%s' to file %s", text, filename)
                     with open(filename, 'w') as f:
-                        f.write(text.encode('utf8'))
-                        f.write(b'\n')
+                        f.write(text + '\n')
 
             new_data = copy.deepcopy(message.data)
             new_data['status'] = "OK"