Fix tests of TrainerCallback (#10615)
Fix tests of TrainerCallback (#10615)

* Fix tests of TrainerCallback

* Update tests/test_trainer_callback.py

Co-authored-by: Lysandre Debut <52471e9cd710b379d379586be3b2a4789b67f916@huggingface.co>
huggingface/transformers,huggingface/transformers,huggingface/transformers,huggingface/pytorch-transformers,huggingface/transformers