[Kernel] Add per-tensor and per-token AZP epilogues

[ProExpertProg]

Added two new epilogues that support int32 azp, one for per-token and per-tensor each. Also added a unit test for folding the AZP correction term into the bias, which is disabled for now due to precision issues.

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[DarkLight1337]

To speed up the CI queue, I've cancelled the distributed tests for the latest CI run in this PR since they won't pass anyway until #5905 has been merged. Now that it has been merged, please merge main into your branch so that the CI can pass once again.

[ProExpertProg]

No problem, thanks for letting me know! This is a draft so there's no rush, will rebase at some point when I'm back from vacation.

[tlrmchlsmth]

It looks like the epilogues are performing the computation:
scale_a * scale_b * Acc + (scale_a * a_zp) * (scale_b * azp_adj)

We will have less rounding error if we instead do:
scale_a * scale_b * (Acc + a_zp * azp_adj)

Do you see any issues with implementing it this way?

[tlrmchlsmth]

Suggest small factoring of TORCH_CHECKs, and a couple of comment fixups. Looks good after that.

[tlrmchlsmth]

/ready