feat: update serialization tests to handle None backbone model type

Author: RaykKretzschmar

tests/test_config.py

@@ -9,7 +9,6 @@
 def test_serialize_deserialize(module: LightningIRModule, tmp_path: Path):
     config = module.model.config
     config_class = module.model.config_class
-    assert config.backbone_model_type == "bert"
     assert config.get_backbone_model_type() == "bert"
     save_dir = str(tmp_path / config_class.model_type)
     config.save_pretrained(save_dir)
@@ -31,4 +30,7 @@ def test_serialize_deserialize(module: LightningIRModule, tmp_path: Path):
                 "_experts_implementation_internal",
             ):
                 continue
+            if key == "backbone_model_type" and value is None:
+                assert new_config.get_backbone_model_type() == config.get_backbone_model_type()
+                continue
             assert getattr(new_config, key) == value

tests/test_model.py

@@ -94,6 +94,9 @@ def test_seralize_deserialize(module: LightningIRModule, tmp_path: Path):
                 "_attn_implementation_autoset",
             ):
                 continue
+            if key == "backbone_model_type" and value is None:
+                assert new_model.config.get_backbone_model_type() == model.config.get_backbone_model_type()
+                continue
             assert getattr(new_model.config, key) == value
         for key, value in model.state_dict().items():
             assert new_model.state_dict()[key].equal(value)