Fix support for image processors modifications in modular
Author: yonigozlan
Pull request: yes

# What does this PR do?

I need to add a method to an existing image processor in the GotOcr2 PR https://github.com/huggingface/transformers/pull/34721
Right now there seems to be a bug where the model name is not correctly deduced from the file name when we inherit from a module in an image_processing* file. With the example added, I get this error:
```
Traceback (most recent call last):
  File "/home/ubuntu/models_implem/transformers/utils/modular_model_converter.py", line 1547, in <module>
    converted_files = convert_modular_file(file_name, args.old_model_name, args.new_model_name)
                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/ubuntu/models_implem/transformers/utils/modular_model_converter.py", line 1483, in convert_modular_file
    wrapper.visit(cst_transformers)
  File "/opt/conda/envs/hf_311_121/lib/python3.11/site-packages/libcst/metadata/wrapper.py", line 204, in visit
    return self.module.visit(visitor)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/conda/envs/hf_311_121/lib/python3.11/site-packages/libcst/_nodes/module.py", line 89, in visit
    result = super(Module, self).visit(visitor)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/conda/envs/hf_311_121/lib/python3.11/site-packages/libcst/_nodes/base.py", line 233, in visit
    visitor.on_leave(self)
  File "/opt/conda/envs/hf_311_121/lib/python3.11/site-packages/libcst/_visitors.py", line 137, in on_leave
    leave_func(original_node)
  File "/home/ubuntu/models_implem/transformers/utils/modular_model_converter.py", line 1199, in leave_Module
    renamed_module = module.visit(renamer)
                     ^^^^^^^^^^^^^^^^^^^^^
  File "/opt/conda/envs/hf_311_121/lib/python3.11/site-packages/libcst/_nodes/module.py", line 89, in visit
    result = super(Module, self).visit(visitor)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/conda/envs/hf_311_121/lib/python3.11/site-packages/libcst/_nodes/base.py", line 227, in visit
    _CSTNodeSelfT, self._visit_and_replace_children(visitor)
                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/conda/envs/hf_311_121/lib/python3.11/site-packages/libcst/_nodes/module.py", line 74, in _visit_and_replace_children
    body=visit_body_sequence(self, "body", self.body, visitor),
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/conda/envs/hf_311_121/lib/python3.11/site-packages/libcst/_nodes/internal.py", line 227, in visit_body_sequence
    return tuple(visit_body_iterable(parent, fieldname, children, visitor))
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/conda/envs/hf_311_121/lib/python3.11/site-packages/libcst/_nodes/internal.py", line 193, in visit_body_iterable
    new_child = child.visit(visitor)
                ^^^^^^^^^^^^^^^^^^^^
  File "/opt/conda/envs/hf_311_121/lib/python3.11/site-packages/libcst/_nodes/base.py", line 236, in visit
    leave_result = visitor.on_leave(self, with_updated_children)
                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/conda/envs/hf_311_121/lib/python3.11/site-packages/libcst/matchers/_visitors.py", line 515, in on_leave
    retval = CSTTransformer.on_leave(self, original_node, updated_node)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/conda/envs/hf_311_121/lib/python3.11/site-packages/libcst/_visitors.py", line 71, in on_leave
    updated_node = leave_func(original_node, updated_node)
                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/ubuntu/models_implem/transformers/utils/modular_model_converter.py", line 122, in leave_ClassDef
    new_name = convert_to_camelcase(updated_node.name.value, self.old_name, self.default_old_name)
                                                                            ^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'ReplaceNameTransformer' object has no attribute 'default_old_name'
```

Things work as expected with the following change:
https://github.com/huggingface/transformers/blob/4e90b99ed916300b80bac9db793f2a96b2a87122/utils/modular_model_converter.py#L1195

to

```python
file_model_name = file.split(".")[-2]
```

As unless I'm missing something, the model name can be deduced from the folder name in which modeling/processing/config files are located?


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