Mac: Update sandbox rules that target 10.13 exactly to target 10.13 and higher.

GPU v1 sandbox removes condition since we don't have the os-version variable there (per offline discussion).

Bug: 879646
Change-Id: I06b29d1c6b4b6fd621a5b2497b0a2b78fe36c85f
Reviewed-on: https://chromium-review.googlesource.com/1200184
Reviewed-by: Robert Sesek <rsesek@chromium.org>
Commit-Queue: Leonard Grey <lgrey@chromium.org>
Cr-Commit-Position: refs/heads/master@{#588135}