change: Update for PT 2.5.1, SMP 2.8.0

[viclzhu]

Description of changes:
Update for PT2.5.1, SMP2.8.0 release

Testing done:
Ran tests/unit/sagemaker/image_uris/test_smp_v2.py locally and it passes.

Merge Checklist

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• I have read the CONTRIBUTING doc
• I certify that the changes I am introducing will be backward compatible, and I have discussed concerns about this, if any, with the Python SDK team
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Tests

• I have added tests that prove my fix is effective or that my feature works (if appropriate)
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