Add a test for llama finetuning with FP8 precision

[scsudhak-intel]

What does this PR do?

Adding example test case for the combination of Llama2-7B + MPI + LoRA + FP8 precision

Fixes # (issue)

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• 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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