fix scaling factor for DeepSeek

[bzgoogle]

Description

fix scaling factor for DeepSeek
We should use yarn based scaling factor for attention score

Tests

tested with offline benchmarking with reasonable accuracy: https://paste.googleplex.com/4921594585284608

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[github-actions]

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[jrplatin]

Are these constants? Does rope_scaling["factor"] ever change? If not, can we move this logic out to the __init__ so we don't waste compute on this?

[bzgoogle]

Done. Moved to post__init