Error with RGBA images
https://huggingface.co/datasets/huggan/few-shot-skulls

```
Status code:   500
Exception:     Status500Error
Message:       cannot write mode RGBA as JPEG
```

reported by @NielsRogge 


Error with RGBA images: https://huggingface.co/datasets/huggan/few-shot-skulls

```
Status code:   500
Exception:     Status500Error
Message:       cannot write mode RGBA as JPEG
```

reported by @NielsRogge 

