Add support for viewing webp images
### Description I've recently switched from PNG to WebP in my project. When viewing the diff of a MR, it will show PNG-files but not WebP-files ("No preview for this file type"). ![image](/uploads/26c3ea1563d33f03657465c0fd52d43f/image.png) ### Proposal Enable showing WebP-files just like any other image. It should be no problem for modern browsers to display it, right. ### Links / references - https://developers.google.com/speed/webp/
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