update get_parameter_dtype

[yiyixuxu]

fix #10337

update dtype so it return floating dype, match the logic in https://github.com/huggingface/transformers/blob/8f38f58f3de5a35f9b8505e9b48985dce5470985/src/transformers/modeling_utils.py#L281

[HuggingFaceDocBuilderDev]

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[hlky]

Edit: was missing to("cuda").