[CI/Build] Add support for Python 3.13

[mgoin]

FIX #12083

Dependencies that are blockers for python 3.13 support:

• xgrammar (issue Python 3.13 wheel mlc-ai/xgrammar#193)
• ray (unsure progress here)
• torchaudio==2.5.1 (resolved by Update to torch==2.6.0 #12721)
• vllm-flash-attn (Add python 3.13 support to CMakeLists.txt flash-attention#47)

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[Ryp]

I think you'd also need a matching PR on https://github.com/vllm-project/flash-attention/blob/main/CMakeLists.txt#L22

Run locally with TORCH_CUDA_ARCH_LIST="Auto" VLLM_BUILD_DIR=build pip install -v --no-clean --no-build-isolation -e . and you should run into the error if you didn't patch this part.

[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. Please rebase the PR, @mgoin.

https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork