2.8 backport PR request list

[pgmoka]

Similar to the backport request thread in 2.5 release #7977

The issue is to track 2.8 release backport. Branch: https://github.com/pytorch/xla/compare/r2.8

For the process:

Tag you PRs with the "backprot2.8" label. For any PRs you want to backport to 2.8, please reply with following:

Original PR link
Reason to backport
2.8 backport PR link

[bhavya01]

Original PR link: #9427
Reason to backport: Update release CI to use 3.12 python versions
2.8 backport PR link: #9485

[bhavya01]

Original PR's: #9443, #9463
Reason to backport: Fix CI tests. _get_stablehlo had a race condition that was exposed by moving to python3.12
2.8 backport link: f49c470

[melissawm]

Original PR link: #9498
Reason to backport: Organize documentation for the 2.8 release
2.8 backport PR link (pending)

[pavithraes]

Original PR link: #9503
Reason to backport: Add new documentation pages, partially related to the release
2.8 backport PR link: (pending)

[bhavya01]

Original PR: #9497
2.8 backport link: #9525
Reason: Fix torchax CI

[pgmoka]

2.8 has been launched