Fix CommonKeys docstring

Signed-off-by: Bartosz Grabowski <[email protected]>

Author: bartosz-grabowski

monai/utils/enums.py

@@ -335,7 +335,7 @@ class CommonKeys(StrEnum):
     `LABEL` is the training or evaluation label of segmentation or classification task.
     `PRED` is the prediction data of model output.
     `LOSS` is the loss value of current iteration.
-    `INFO` is some useful information during training or evaluation, like loss value, etc.
+    `METADATA` is some useful information during training or evaluation, like loss value, etc.
 
     """