Fix is_torch_tpu_available in ORT Trainer

[regisss]

What does this PR do?

Following #2012. There is one occurrence of is_torch_tpu_available in the code of the ORTTrainer class, which will fail for transformers >= 4.39.0.

Before submitting

• This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
• Did you make sure to update the documentation with your changes?
• Did you write any new necessary tests?

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[HuggingFaceDocBuilderDev]

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[IlyasMoutawwakil]

LGTM thanks for the fix !