fix README

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Author: weifengpy

distributed/FSDP2/README.md

@@ -4,7 +4,7 @@ To run FSDP2 on transformer model:
 cd distributed/FSDP2
 torchrun --nproc_per_node 2 train.py
 ```
-* For 1st time, it creates a "checkpoints" folder and save state dicts there
+* For 1st time, it creates a "checkpoints" folder and saves state dicts there
 * For 2nd time, it loads from previous checkpoints
 
 To enable explicit prefetching