Remove sophiechang from opt guide watchlist

This is redundant for me since I'm on breve-team-reviews@chromium.org and do not need this to personally cc me.

Change-Id: I5d330ce512b813c6803efbbf2b5b7f0724c3db2d
Reviewed-on: https://chromium-review.googlesource.com/c/1387835Reviewed-by: Doug Arnett <dougarnett@chromium.org>
Commit-Queue: Sophie Chang <sophiechang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#618334}

WATCHLISTS

@@ -2349,8 +2349,7 @@
                       'petewil+watch@chromium.org',
                       'romax+watch@chromium.org'],
     'omnibox': ['jdonnelly+watch@chromium.org'],
-    'optimization_guide': ['dougarnett+watch-optguide@chromium.org',
-                           'sophiechang+watch-optguide@chromium.org'],
+    'optimization_guide': ['dougarnett+watch-optguide@chromium.org'],
     'origin_trials': ['chasej+watch@chromium.org',
                       'iclelland+watch@chromium.org'],
     'ozone': ['kalyan.kondapally@intel.com',