StableDiffusionInpaintPipeline missing from_single_file

[ballenvironment]

Is your feature request related to a problem? Please describe.
The inpaint pipeline is missing from_single_file method, which is inconsistent with the other pipelines.

Describe the solution you'd like

generator = StableDiffusionInpaintPipeline.from_single_file(model)

Describe alternatives you've considered
I'm currently doing this as an alternative, but it's ugly code.

generator = StableDiffusionImg2ImgPipeline.from_single_file(model)
saved_vae = generator.vae
saved_text_encoder = generator.text_encoder
saved_tokenizer = generator.tokenizer
saved_unet = generator.unet
saved_scheduler = generator.scheduler
saved_safety_checker = generator.safety_checker
saved_feature_extractor = generator.feature_extractor
generator = StableDiffusionInpaintPipeline(vae=saved_vae, text_encoder=saved_text_encoder, tokenizer=saved_tokenizer, 
            unet=saved_unet, scheduler=saved_scheduler, safety_checker=saved_safety_checker, feature_extractor=saved_feature_extractor)

Additional context
Add any other context or screenshots about the feature request here.

[sayakpaul]

If we check here:

https://github.com/huggingface/diffusers/blob/6632823690707604ef364e4d2fa02269bf1a7d07/src/diffusers/pipelines/stable_diffusion/pipeline_stable_diffusion_img2img.py#L102C70-L102C89

the StableDiffusionImg2ImgPipeline is being subclassed from FromSingleFileMixin as well which is not the case for StableDiffusionInpaintPipeline:

https://github.com/huggingface/diffusers/blob/6632823690707604ef364e4d2fa02269bf1a7d07/src/diffusers/pipelines/stable_diffusion/pipeline_stable_diffusion_inpaint.py#L156C7-L156C37

Would you maybe like to open a PR to help us improve this?

[patrickvonplaten]

Fixed in #4041

[ballenvironment]

Much appreciated!