[fix] log_dir with W&B

[tcapelle]

redirect log_dir to wandb.init(..., dir=log_dir)

[pytorch-bot]

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[RdoubleA]

Can you verify that a command like tune run lora_finetune_single_device --config llama2/7B_lora_single_device metric_logger=torchtune.utils.metric_logging.WandBLogger log_every_n_steps=1 metric_logger.project=my-project runs without error now?

And please run pytest tests --with-integration as a sanity check :)

[RdoubleA]

nit: should explain what's used if this is not specified (or if dir is specified)

[RdoubleA]

Can you verify that a command like tune run lora_finetune_single_device --config llama2/7B_lora_single_device metric_logger=torchtune.utils.metric_logging.WandBLogger log_every_n_steps=1 metric_logger.project=my-project

verified that this runs successfully

wandb: WARNING Path /tmp/lora_finetune_output/wandb/ wasn't writable, using system temp directory.
wandb: WARNING Path /tmp/lora_finetune_output/wandb/ wasn't writable, using system temp directory