Remove martiw@, ramyasharma@ from OWNERS of iOS bookmarks.

Bug: None
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Change-Id: I19ac155dd3d809ccd5e770dc67fc5db5dc4679a2
Reviewed-on: https://chromium-review.googlesource.com/923505
Commit-Queue: Eric Noyau <noyau@chromium.org>
Reviewed-by: Eric Noyau <noyau@chromium.org>
Cr-Commit-Position: refs/heads/master@{#537299}

ios/chrome/browser/ui/bookmarks/OWNERS

 noyau@chromium.org
 lpromero@chromium.org
-ramyasharma@chromium.org
-martiw@chromium.org
 
 # TEAM: ios-directory-owners@chromium.org
 # OS: iOS