Add feature extraction mapping for automatic metadata update (#28944)

* add feature extraction mapping

* added prefix

* ruff check

* minor fix

* Update modeling_auto.py

* fix typo

* remove prefix to make variable public/importable

* Update src/transformers/models/auto/modeling_auto.py

Co-authored-by: amyeroberts <22614925+amyeroberts@users.noreply.github.com>

* fixes

* addressed comments

* nit

* fix-copies

* remove from tests

* this should fix

* Update tests/models/convnextv2/test_modeling_convnextv2.py

Co-authored-by: amyeroberts <22614925+amyeroberts@users.noreply.github.com>

* nits

---------

Co-authored-by: amyeroberts <22614925+amyeroberts@users.noreply.github.com>

tests/test_modeling_common.py

@@ -700,7 +700,10 @@ class ModelTesterMixin:
         for model_class in self.all_model_classes:
             if (
                 model_class.__name__
-                in [*get_values(MODEL_MAPPING_NAMES), *get_values(MODEL_FOR_BACKBONE_MAPPING_NAMES)]
+                in [
+                    *get_values(MODEL_MAPPING_NAMES),
+                    *get_values(MODEL_FOR_BACKBONE_MAPPING_NAMES),
+                ]
                 or not model_class.supports_gradient_checkpointing
             ):
                 continue