[`Hub`] Add `safe_serialization` in push_to_hub
# What does this PR do?

This PR adds the possibility to directly push safetensors weight on the Hub, as the `save_pretrained` method was called with default args and it is currently not possible to pass kwargs to use `safe_serialization=True`.

cc @sgugger @Narsil 

Related: https://github.com/huggingface/peft/pull/553

also cc @pacman100 
_The documentation is not available anymore as the PR was closed or merged._