Add a bot for AVIF

Builds and tests the code with skia_use_libavif = true.

Bug: b/240344467
Change-Id: Ia40dccc26573802628775d309cf18c23d4e840f3
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/566444
Reviewed-by: Leon Scroggins <scroggo@google.com>
Commit-Queue: Leon Scroggins <scroggo@google.com>
6 files changed