Fix datasets set_format
# What does this PR do?

This PR fixes a problem in `Trainer` when user provide a dataset using the new functionality in the upcoming v2 of `datasets` `set_transform` (see [here](https://github.com/huggingface/datasets/issues/1867) for more details). This is a hotfix that is not perfect and we will need to take some time to make this column ignoring more general (probably after batch creation) but I will look deeper into this at the end of next week.