add dreambooth methods for tuning full weights of sdxl.

[AY-Liu]

What does this PR do?

add dreambooth methods for tuning full weights of sdxl.

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[sayakpaul]

I don't think the full fine-tuning script for DreamBoothing with SDXL will be as impactful as its LoRA counterpart. So, I am a little hesitant here. WDYT @yiyixuxu?

[bghira]

dreambooth with DoRA is actually going to perform better than this would

[github-actions[bot]]

This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

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[sayakpaul]

Closing this because of inactivity.