fix a bug of `prompt embeds` in sdxl (#4099)
* fix bug in sdxl
* Update pipeline_stable_diffusion_xl_img2img.py
* Update pipeline_stable_diffusion_xl.py
* Update pipeline_stable_diffusion_xl_img2img.py
* Update pipeline_stable_diffusion_xl_inpaint.py
* Update pipeline_stable_diffusion_xl.py
* Update pipeline_stable_diffusion_xl_img2img.py
* Update pipeline_stable_diffusion_xl_inpaint.py
* Update pipeline_stable_diffusion_xl_img2img.py
* Update pipeline_controlnet_sd_xl.py
* Update pipeline_controlnet_sd_xl.py
* Update pipeline_stable_diffusion_xl.py
* Update pipeline_stable_diffusion_xl_img2img.py
* Update pipeline_stable_diffusion_xl_inpaint.py
* Update test_stable_diffusion_xl.py
* Update test_stable_diffusion_xl.py
* Update test_stable_diffusion_xl.py
add test on prompt_embeds
* add test on prompt_embeds
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Co-authored-by: Patrick von Platen <patrick.v.platen@gmail.com>