Remove eugenebut from ios/chrome/browser/itunes_urls owners

Bug: None
Change-Id: I29a3862af76bb103713374ca2b06d8172eca1d72
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2633852
Auto-Submit: Eugene But <eugenebut@chromium.org>
Commit-Queue: Mohammad Refaat <mrefaat@chromium.org>
Reviewed-by: Mohammad Refaat <mrefaat@chromium.org>
Cr-Commit-Position: refs/heads/master@{#845348}

ios/chrome/browser/itunes_urls/OWNERS

-eugenebut@chromium.org
 mrefaat@chromium.org