[ios] Adds sczs@ as c/b/ui/settings OWNER

Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Change-Id: I1e164941fe2a1a6e51bb33f816fdb8ffb6b11d54
Reviewed-on: https://chromium-review.googlesource.com/1024238Reviewed-by: Rohit Rao <rohitrao@chromium.org>
Reviewed-by: Mark Cogan <marq@chromium.org>
Commit-Queue: Sergio Collazos <sczs@chromium.org>
Cr-Commit-Position: refs/heads/master@{#553125}

ios/chrome/browser/ui/settings/OWNERS

 edchin@chromium.org
-lpromero@chromium.org
+sczs@chromium.org
 sdefresne@chromium.org
 
 # TEAM: ios-directory-owners@chromium.org