Request: Support webp icons on Android

[raldred]

Android studio's Image Asset Studio defaults to generating webp icons.

I am able to pass the glob of the source files to add_badge

add_badge(
      shield: "staging-#{version}-orange",
      alpha_channel: true,
      custom: '../staging-badge.png',
      glob: "./android/app/src/main/res/mipmap-*/ic_launcher.webp",
 )

However the generation is hardcoded to output "png"

Could we get an option to specify the output format to webp? I believe imagemagic can output a composite image made up of different source formats?