* [fix] make legacy bnb code work
* [fix] use get with default instead of getter
* add test for bnb 8bit optim skip embed
* [fix] style
* add require annotation of bnb
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Co-authored-by: jaycha <jaycha@ncsoft.com>
Co-authored-by: Marc Sun <57196510+SunMarc@users.noreply.github.com>