Fix `StableDiffusionXLImg2ImgPipeline` creation in sdxl tutorial (#5367)

fix: StableDiffusionXLImg2ImgPipeline creation in sdxl tutorial

docs/source/en/using-diffusers/sdxl.md

@@ -39,7 +39,7 @@ pipeline = StableDiffusionXLPipeline.from_pretrained(
     "stabilityai/stable-diffusion-xl-base-1.0", torch_dtype=torch.float16, variant="fp16", use_safetensors=True
 ).to("cuda")
 
-refiner = StableDiffusionXLImg2ImgPipeline.from_single_file(
+refiner = StableDiffusionXLImg2ImgPipeline.from_pretrained(
     "stabilityai/stable-diffusion-xl-refiner-1.0", torch_dtype=torch.float16, use_safetensors=True, variant="fp16"
 ).to("cuda")
 ```