feat: Apply RoPE embedding with sequence offsets

[sudhakarsingh27]

What does this PR do ?

Allows applying rope embedding with "offsets" to sequences in packed (thd) or batch (bshd/sbhd) formats. The offset per sequence can be supplied as an argument start_positions tensor.

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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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[deepakn94]

/ok to test c3e83ad

[sudhakarsingh27]

/ok to test

[sudhakarsingh27]

/ok to test f0461ab

[sudhakarsingh27]

/ok to test 58ba726

[sudhakarsingh27]

/ok to test 76b60a8

[sudhakarsingh27]

/ok to test bb95919

[BoxiangW]

Can you also add a test for TE >= 2.10? With something like

@pytest.mark.skipif(
    not is_te_min_version("2.10.0", check_equality=True),
    reason="Requires TransformerEngine >= 2.10.0",
)