Use "set noparent" in testing/buildbot/OWNERS to make it effective

testing/OWNERS has * in it.

Example CL where this made a difference: https://codereview.chromium.org/246623009/

BUG=none
R=sky@chromium.org

Review URL: https://codereview.chromium.org/289863006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@271641 0039d316-1c4b-4281-b951-d872f2087c98

testing/buildbot/OWNERS

+# This is needed because of * in testing/OWNERS .
+set noparent
+
 darin@chromium.org
 phajdan.jr@chromium.org
 sky@chromium.org