custom checkpoint in trainer.py
Author: mzamini92
Pull request: yes

I was wondering can we do like this? `_custom_save_checkpoint` is that it provides more control and flexibility for customizing how checkpoints are saved. You can define your own naming conventions and include or exclude specific information in the checkpoint. This can be useful if you have specific requirements or want to integrate with external systems or tools that expect a certain checkpoint format. In contrast, `_tune_save_checkpoint` is designed specifically for use with Ray Tune and follows Ray Tune's conventions for managing checkpoints. It may be more convenient when we are using Ray Tune for hyperparameter tuning and need to manage checkpoints in a standardized way.

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Comments:
cc @muellerzr and @pacman100 

I'm pretty sure the naming conventions we are are standardized and immutable for the filenames, so I'm not sure this is a venture we want to go down unless I'm mistaken (cc @ArthurZucker trainer doesn't support custom model names due to integrating with everything else, right?) 

This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

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