[rn] Support UINT8 type for onnxruntime-react-native on iOS (#13210)
### Description
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As title.
### Motivation and Context
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- If it fixes an open issue, please link to the issue here. -->
Uint8 type might be required for some model used in sample application.
To match supported data types for onnxruntime-react-native for Android.
Co-authored-by: rachguo <rachguo@rachguos-Mac-mini.local>
Co-authored-by: rachguo <rachguo@rachguos-Mini.attlocal.net>