[Core] fix: legacy model mapping (#8416)

* fix: legacy model mapping

* remove print

src/diffusers/models/modeling_utils.py

@@ -1057,6 +1057,9 @@ class LegacyModelMixin(ModelMixin):
         # To prevent depedency import problem.
         from .model_loading_utils import _fetch_remapped_cls_from_config
 
+        # Create a copy of the kwargs so that we don't mess with the keyword arguments in the downstream calls.
+        kwargs_copy = kwargs.copy()
+
         cache_dir = kwargs.pop("cache_dir", None)
         force_download = kwargs.pop("force_download", False)
         resume_download = kwargs.pop("resume_download", None)
@@ -1094,4 +1097,4 @@ class LegacyModelMixin(ModelMixin):
         # resolve remapping
         remapped_class = _fetch_remapped_cls_from_config(config, cls)
 
-        return remapped_class.from_pretrained(pretrained_model_name_or_path, **kwargs)
+        return remapped_class.from_pretrained(pretrained_model_name_or_path, **kwargs_copy)