Fix token dispatched cudagraph_attrs

[asolergi-nv]

What does this PR do ?

When using cuda graphs, some cudagraph_attrs reference attributes from objects of the token dispatcher (e.g. _comm_manager.token_probs) which can't be accessed directly from the top module.

The fix is very simple: Access the attributes one by one (e.g. first _comm_manager, then _comm_manager.token_probs).

It's curious because in another part of the code we do access these attributes correctly.

Megatron-LM/megatron/core/transformer/transformer_layer.py

Lines 1091 to 1096 in 027e0f3

	for i, attr_name in enumerate(valid_cudagraph_attrs):
	hier_attr_name = attr_name.split('.')
	attr = self.mlp.token_dispatcher
	for name in hier_attr_name[:-1]:
	attr = getattr(attr, name)
	setattr(attr, hier_attr_name[-1], attr_outputs[i])

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[asolergi-nv]

/ok to test cef1302