Update transformer-engine dependency to version 2.15.0

[balasaajay]

What does this PR do ?

Update transformer-engine dependency to version 2.15.0 and adjust related references in pyproject.toml and uv.lock

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[balasaajay]

/ok to test 3c53811

[balasaajay]

/ok to test dc6e056

[balasaajay]

/ok to test dc6e056

[balasaajay]

/ok to test 9546e1c

[balasaajay]

/ok to test 9546e1c