Features:
 - Added support for decoding 10-bit and 12-bit AVIF
 - Initial, opt-in serde support for an enum. This may be extended to other types in the future.

Bug fixes:
 - [Multiple bug fixes in AVIF decoding](https://github.com/image-rs/image/pull/2373)
 - The `rayon` feature now correctly toggles the use of `rayon` when encoding AVIF. (Previously it would be either always on or always off depending on the version of the `ravif` crate in your dependency tree.)
 - "jfif" file extension for JPEG images is now recognized