Automatic batch size using accelerate

[juletx]

It would be great to add an option to select batch size automatically using accelerate find_executable_batch_size function:
https://huggingface.co/docs/accelerate/main/en/package_reference/utilities#accelerate.find_executable_batch_size

[VikParuchuri]

I'm not planning to include this in the core marker (I don't want to bloat the library), but it would be easy to write an external utility that does this