[`Accelerator`] Fix issue with 8bit models (#1155)
* fix 8bit models on `accelerate`
* add bnb as dependency
* Apply suggestions from code review
Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>
* fix
* skip a test
* make style
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Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>
