Manager independent from submitit

[lucas-maes]

Need only to implement checkpoint method and remove submitit from the dependencies in pyproject.toml

https://github.com/facebookincubator/submitit/blob/main/submitit/helpers.py

def checkpoint(self, *args: tp.Any, **kwargs: tp.Any) -> DelayedSubmission:
        """Resubmits the same callable with the same arguments"""
        # The DelayedSubmission class goal is only to register and format
        # the arguments of the call "self(*args, **kwargs)" for submission to slurm
        return DelayedSubmission(self, *args, **kwargs)  # type: ignore