Fix MLflowCallback and add support for MLFLOW_EXPERIMENT_NAME (#17091)
Fix MLflowCallback and add support for MLFLOW_EXPERIMENT_NAME (#17091)

* Fix use of mlflow.active_run() and add proper support for MLFLOW_EXPERIMENT_NAME

* Fix code style (make style)
huggingface/transformers,huggingface/transformers,huggingface/transformers,huggingface/transformers