SD3 inpaint pipeline can not use EulerA scheduler. bug: The `scale_model_input` function should be called before `step` to ensure correct denoising.

### Describe the bug

SD3 inpaint pipeline can not use EulerA scheduler.

### Reproduction

```python
pipe = StableDiffusion3InpaintPipeline.from_pretrained(xxx)
pipe.scheduler = EulerAncestralDiscreteScheduler.from_config(pipe.scheduler.config)

# then run the pipe
out_images = pipe(
prompt=caption,
image=input_image,
mask_image=input_mask, ).images
```

### Logs

```shell
The `scale_model_input` function should be called before `step` to ensure correct denoising. See `StableDiffusionPipeline` for a usage example.
```

### System Info

torch: 2.0.0 + cu117
diffusers: commit_id: `41b705f42db6ce43bbcb41bd2cefd479d8b73774`

### Who can help?

_No response_

Start with StableDiffusion3InpaintPipeline and trace its denoising loop, then compare the scheduler usage with the StableDiffusionPipeline example named in the warning. Reproduce the issue using EulerAncestralDiscreteScheduler and confirm that the pipeline performs the required input scaling before stepping without the warning.

Scritto dal modello di indicizzazione a partire dal testo della issue.