ci: Bump GHA versions

[chtruong814]

What does this PR do ?

ci: Bump GHA versions

Still seeing some github actions with the warning about using an older node version. Bumping the GHA versions that I can find to resolve.

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[chtruong814]

/ok to test 9857ec6

[chtruong814]

/ok to test 0690d55

[chtruong814]

/ok to test f9f197e

[svcnvidia-nemo-ci]

🔄 Merge queue validation started!

You can track the progress here: https://github.com/NVIDIA/Megatron-LM/actions/runs/25555041371