add PAG support for SD Img2Img

[SahilCarterr]

What does this PR do?

Adds PAG (Perturbed-Attention Guidance) support for SD models (StableDiffusionPAGImg2ImgPipeline).Continuation of #7944

Fixes #8710 (partially)

Before submitting

• This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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• Did you write any new necessary tests?

Who can review?

@yiyixuxu
Anyone in the community is free to review the PR once the tests have passed.

---

Usage

from diffusers import AutoPipelineForImage2Image
from diffusers.utils import load_image, make_image_grid
import torch

# Set device to CUDA for GPU processing
device = "cuda"

# Load the image-to-image pipeline with pre-trained weights
pipe = AutoPipelineForImage2Image.from_pretrained("Lykon/dreamshaper-8", enable_pag=True)
pipe.to(device)

# Load an initial image
init_image = load_image(
    "https://huggingface.co/datasets/huggingface/documentation-images/resolve/main/diffusers/cat.png"
)

# Set a random generator with a specific seed
generator = torch.Generator("cuda").manual_seed(31)

# Define the prompt
prompt = "cat wizard"

# Generate the output image using the pipeline
image = pipe(prompt, image=init_image, generator=generator, pag_scale=0.4).images[0]

# Create a grid of the initial and generated images
make_image_grid([init_image, image], rows=1, cols=2)

[yiyixuxu]

thanks! I left some comments
can we see some outputs too? (saw it)!

[yiyixuxu]

don't forget to call make style and make fix-copies too

[SahilCarterr]

added "# copied from" , removed depreciated methods and fix test

[yiyixuxu]

thanks! I think we still have one test needs to be removed, and then can merge!

[yiyixuxu]

this test is not needed? (same as the one above it?)

[SahilCarterr]

should i remove StableDiffusionPAGImg2ImgPipelineIntegrationTests(unittest.TestCase): also ?

[HuggingFaceDocBuilderDev]

The docs for this PR live here. All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.

[yiyixuxu]

@SahilCarterr can you look into failing tests?

[SahilCarterr]

3 errors remaining to be fix

[SahilCarterr]

Help Needed to fix the remaining errors

[SahilCarterr]

The errors are now fixed @yiyixuxu