[Birch] Add Release Notes JSON Icon.

Bug: b/330595065
Change-Id: I5ea94f53159604d9173ff197b213189387ca05fd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5403464


Commit-Queue: Ana Salazar <anasalazar@chromium.org>
Auto-Submit: Owen Zhang <owenzhang@google.com>
Reviewed-by: Ana Salazar <anasalazar@chromium.org>
Reviewed-by: Ahmed Fakhry <afakhry@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1280546}