GitLab

* test permission

* Add cross attention type for Sana-Sprint.

* Add Sana-Sprint training script in diffusers.

* make style && make quality;

* modify the attention processor with `set_attn_processor` and change `SanaAttnProcessor3_0` to `SanaVanillaAttnProcessor`

* Add import for SanaVanillaAttnProcessor

* Add README file.

* Apply suggestions from code review

* style

* Update examples/research_projects/sana/README.md

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Co-authored-by: lawrence-cj <cjs1020440147@icloud.com>
Co-authored-by: Sayak Paul <spsayakpaul@gmail.com>