build(before-code-freeze): Fix manylinux Python version

[mc-nv]

What does the PR do?

Fix the Python version used for the manylinux build.

Checklist

• PR title reflects the change and is of format <commit_type>: <Title>
• Changes are described in the pull request.
• Related issues are referenced.
• Populated github labels field
• Added test plan and verified test passes.
• Verified that the PR passes existing CI.
• Verified copyright is correct on all changed files.
• Added succinct git squash message before merging.
• All template sections are filled out.

Commit Type:

• build

Related PRs:

• build(before-code-freeze): Align CMake configuration with the other repos common#162
• build(before-code-freeze): Prepare the ONNX Runtime backend for the manylinux base onnxruntime_backend#352
• build(before-code-freeze): Export the stub's dynamic symbols when libpython is static python_backend#451
• build(before-code-freeze): Build against latest upstream container server#8918

Where should the reviewer start?

The build configuration diff.

Test plan:

Covered by the internal RHEL/manylinux pipeline for the 26.08 upstream bump.

• CI Pipeline ID: 61271932

Caveats:

None known.

Background

Part of the 26.08 "build against latest upstream container" work: the base image
moved to cuda:13.4-devel-manylinux--26.08, which changed the default GCC
toolset, the Python layout and the bundled OpenSSL.

Related Issues: (use one of the action keywords Closes / Fixes / Resolves / Relates to)

• Resolves: TRI-1650

^{CI (internal): [#61271932](http://tritonserver.local/ci/pipelines/61271932)}

[mc-nv]

@greptileai review

[greptile-apps]

Greptile Summary

Updates the RHEL/manylinux build paths from CPython 3.12.1 to 3.12.13 for the 26.08 upstream container.

• Changes the Python site-packages path used to copy PyTorch libraries and headers.
• Changes the x86_64 CPython library path used to copy supporting libraries.

Confidence Score: 5/5

The PR appears safe to merge.

No blocking failure remains.

Important Files Changed

Filename	Overview
CMakeLists.txt	Updates both hardcoded RHEL/manylinux CPython paths consistently to version 3.12.13; no follow-up-eligible defect was identified.

_{Reviews (2): Last reviewed commit: "build: Fix manylinux Python version" | Re-trigger Greptile}