Repository: huggingface/transformers
Pull request: Reduce verbosity for `average_tokens_across_devices=True` and `world size = 1`

# What does this PR do?

Averaging a single value is not strictly speaking incorrect. So I suggest rephrasing, and reducing the level to info. This removes recurring warnings when True is used as the default for this argument.

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Changed files:
filename: src/transformers/training_args.py
patch: @@ -1762,9 +1762,8 @@ def __post_init__(self):
         if self.average_tokens_across_devices:
             try:
                 if self.world_size == 1:
-                    logger.warning(
-                        "average_tokens_across_devices is set to True but it is invalid when world size is"
-                        "1. Turn it to False automatically."
+                    logger.info(
+                        "average_tokens_across_devices is True but world size is 1. Setting it to False automatically."
                     )
                     self.average_tokens_across_devices = False
             except ImportError as e: