Lora bias(enable_lora_bias) deprecate warning

[ashwin-phadke]

Purpose

Add a deprecation warning logger to eventually remove LoRA bias and cleanup the code as well.
Relates to Step 1 of #23892 to add a warning log.

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• [x ] The purpose of the PR, such as "Fix some issue (link existing issues this PR will resolve)".
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[gemini-code-assist]

Code Review

This pull request adds a deprecation warning for the enable_lora_bias option in LoRAConfig. The changes correctly update the docstrings and CLI help text to reflect this deprecation. However, the implementation of the warning in LoRAConfig.__post_init__ includes a redundant logging call alongside warnings.warn, which could lead to duplicate messages for the user. My review includes a suggestion to remove this redundancy for better consistency and user experience.

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[yewentao256]

LGTM, thanks for the work!

[ashwin-phadke]

Curious, @jeejeelee do PR raisers don't have merge request? Or is it available only after the ready tag?

[jeejeelee]

PR submitters typically don't have direct merge permissions and need to go through code review before being merged by authorized members