[ONNX] Do not run 'deduplicate_initializers' when 'keep_initializers_as_inputs' is True (#96320)
### Proposal
When arg of 'keep_initializers_as_inputs' is True, it's quite possible that parameters are set by initializer of input.
Hence we should disable de-duplicate initializer optimization when 'keep_initializers_as_inputs==True'.
- [x] Update doc related to `keep_initializers_as_inputs`.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/96320
Approved by: https://github.com/abock, https://github.com/thiagocrepaldi
