Fix emerging optimizer init_group for ckpt loading

[FDecaYed]

What does this PR do ?

Recent Emerging-Optimizers changes added skip_non_grad_params to _init_group. Megatron checkpoint initialization needs to explicitly disable skipping so optimizer state is fully initialized when loading/restoring checkpoints.

• Update emerging optimizer checkpoint-state initialization to call _init_group(..., skip_non_grad_params=False) so state is created for params that do not yet have grads during checkpoint restore.
• Bump the emerging_optimizers dependency pin to bc634ff8c0cf4fb5dbae0a531081281b499be3a0 to pick up the new skip_non_grad_params option.

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[FDecaYed]

/ok to test 7496370

[skyw]

LGTM

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