[SDXL Inpaint] Correct strength default (#4858)

src/diffusers/pipelines/stable_diffusion_xl/pipeline_stable_diffusion_xl_inpaint.py

@@ -892,7 +892,7 @@ class StableDiffusionXLInpaintPipeline(DiffusionPipeline, LoraLoaderMixin, FromS
         mask_image: PipelineImageInput = None,
         height: Optional[int] = None,
         width: Optional[int] = None,
-        strength: float = 1.0,
+        strength: float = 0.9999,
         num_inference_steps: int = 50,
         denoising_start: Optional[float] = None,
         denoising_end: Optional[float] = None,
@@ -944,7 +944,7 @@ class StableDiffusionXLInpaintPipeline(DiffusionPipeline, LoraLoaderMixin, FromS
                 The height in pixels of the generated image.
             width (`int`, *optional*, defaults to self.unet.config.sample_size * self.vae_scale_factor):
                 The width in pixels of the generated image.
-            strength (`float`, *optional*, defaults to 1.):
+            strength (`float`, *optional*, defaults to 0.9999):
                 Conceptually, indicates how much to transform the masked portion of the reference `image`. Must be
                 between 0 and 1. `image` will be used as a starting point, adding more noise to it the larger the
                 `strength`. The number of denoising steps depends on the amount of noise initially added. When