[Main] fix cg missing wgrad hook

[Wohox]

What does this PR do ?

This PR fixes the missing backward post hook bug, this bug happens when delay_wgrad_compute and cuda_graph are both enabled, the parameters within delayed wgrad computation scope will skip the backward post hook.

The fix is in TE, this PR only adds version guard and several flag assertions.
Related TE PR: NVIDIA/TransformerEngine#2614
PR for dev: #2999

Contribution process

flowchart LR
    A[Pre-checks] --> B[PR Tests]
    subgraph Code Review/Approval
        C1[Expert Review] --> C2[Final Review]
    end
    B --> C1
    C2 --> D[Merge]

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