Fix the missing parameter error when running mp_imagenet with torchrun #5729
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Currently the test (
PJRT_DEVICE=GPU torchrun --nproc_per_node=4 --nnodes=1 --node_rank=1 --rdzv_endpoint="10.164.0.13:12355" pytorch/xla/test/test_train_mp_imagenet.py --fake_data --pjrt_distributed --batch_size=128 --num_epochs=1) fails with error:This PR fixes it.