WordPress.com REST API: consider supporting AVIF as a supported media type

[Jeremy Herve]

Core recently enabled AVIF uploads:

https://core.trac.wordpress.org/ticket/53167

We should consider better support for AVIF in our APIs, even if Photon itself does not yet support AVIF: #35432

jetpack/projects/plugins/jetpack/class.json-api-endpoints.php

Line 1624 in e3d2922

 if ( in_array( $ext, array( 'jpg', 'jpeg', 'png', 'gif', 'webp' ), true ) ) { 

jetpack/projects/plugins/jetpack/sal/class.json-api-post-base.php

Line 941 in a1830e4

 if ( in_array( $ext, array( 'jpg', 'jpeg', 'png', 'gif', 'webp' ), true ) ) { 

jetpack/projects/plugins/jetpack/functions.global.php

Line 396 in e9150a3

 'jetpack_supported_media_sideload_types', 

jetpack/projects/plugins/jetpack/modules/videopress/js/videopress-plupload.js

Lines 246 to 247 in 4fe0df9

 // Handle early mime type scanning for images. 
 image = /(?:jpe?g|png|gif|webp)$/i.exec( file.name );