[ Kernel ] FP8 Dynamic Per Token Quant - Add scale_ub

[varun-sundar-rabindranath]

Update FP8 dynamic per token quantization kernels to have scale_ub inputs

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[github-actions]

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[mgoin]

LGTM just have my nit on making scale_ub default to None

[varun-sundar-rabindranath]

I am comparing our kernels with the FBGemm quant kernels right now. Unfortunately, we can't compare them in unit tests as FBGemm requires the nightly pytorch. Ill mark the PR ready when I see correctness.

[varun-sundar-rabindranath]

/ready

[mgoin]

Great work!