fix default getattr

tests/test_modeling_common.py

@@ -117,7 +117,7 @@ class ModelTesterMixin:
 
     def test_attention_outputs(self):
         config, inputs_dict = self.model_tester.prepare_config_and_inputs_for_common()
-        seq_len = self.model_tester.seq_length
+        seq_len = getattr(self.model_tester, "seq_length", None)
         decoder_seq_length = getattr(self.model_tester, "decoder_seq_length", seq_len)
         encoder_seq_length = getattr(self.model_tester, "encoder_seq_length", seq_len)
         decoder_key_length = getattr(self.model_tester, "key_length", decoder_seq_length)