Bump NCCL-EP submodule commit

[phu0ngng]

Description

To include EM-Pull-Push

Type of change

• Documentation change (change only to the documentation, either a fix or a new content)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Infra/Build change
• Code refactoring

Changes

Please list the changes introduced in this PR:

• Change A
• Change B

Checklist:

• I have read and followed the contributing guidelines
• The functionality is complete
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[phu0ngng]

/te-ci L1 pytorch

[greptile-apps]

Greptile Summary

Updates the pinned NVIDIA NCCL Extensions submodule revision to include EM-Pull-Push.

• Advances 3rdparty/nccl-extensions from commit 9f47d6eb to 6a81bce7.
• Makes no direct changes to Transformer Engine source code or build configuration.

Confidence Score: 5/5

The PR appears safe to merge because no concrete build, runtime, or security failure was identified from the submodule revision update.

The change only advances the NCCL Extensions gitlink, and the available evidence does not establish an incompatible artifact layout, API contract, or runtime behavior.

Important Files Changed

Filename	Overview
3rdparty/nccl-extensions	Advances the NCCL Extensions submodule pointer; no concrete compatibility or correctness defect was established.

_{Reviews (1): Last reviewed commit: "bump nccl ep" | Re-trigger Greptile}