Fix bug ORTModelForFeatureExtraction (#2267)
* Fix bug ORTModelForFeatureExtraction
* Update optimum/onnxruntime/modeling_ort.py
Co-authored-by: Ilyas Moutawwakil <57442720+IlyasMoutawwakil@users.noreply.github.com>
* Update optimum/onnxruntime/modeling_ort.py
* return_dict support for ORTModelForxxx
* Add _warn_on_unhandled_inputs helper method to ORTModel
* Add test for the return_dict feature
* fix style
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Co-authored-by: Ilyas Moutawwakil <57442720+IlyasMoutawwakil@users.noreply.github.com>
