Some Lossless WebP files can not be decoded and therefore used

### Tested versions

- Reproducable in Godot 4.6.1

### System information

Godot v4.6.1.stable - Windows 11 (build 26100) - Multi-window, 4 monitors - Vulkan (Forward+) - dedicated AMD Radeon RX 6900 XT (Advanced Micro Devices, Inc.; 32.0.21041.1000) - AMD Ryzen 9 5900X 12-Core Processor (24 threads) - 31.92 GiB memory

### Issue description

Some WebP Images do not work in Godot. There is always this error:
```
ERROR: Failed decoding WebP image.
ERROR: core/io/image_loader.cpp:100 - Error loading image: 'res://background.webp'.
ERROR: Error importing 'res://background.webp'.
```

All of the issues are created with Aseprite 1.3.16.1.

What I found out so far:
- They all works with Chromium, Aseprite and on Windows Image Viewer
- If a high compression level does not work, then most of the lower ones work. Sometimes 0 compression level does not work, while e.g. 1 works.
- It seems that bigger images with non pixel art suffer from this. But not all of them

### Steps to reproduce

- Open the attached project, in there are images that do not work
- Some images work with another compression levels, which I added as well

### Minimal reproduction project (MRP)

[webp-decoder.zip](https://github.com/user-attachments/files/25351612/webp-decoder.zip)

Start with the attached webp-decoder.zip minimal reproduction project and the error location in core/io/image_loader.cpp:100. Compare the failing and working WebP files and verify that the affected images import and decode successfully without the reported errors.

Written by the indexing model from the issue text.