Add instructions for pushing TestResultServer and GardeningServer.

NOTRY=true
r=pdr@chromium.org,szager@chromium.org

Review URL: https://codereview.chromium.org/437443002

git-svn-id: svn://svn.chromium.org/blink/trunk@179274 bbb929c8-8fbe-4397-9dbb-9b2b20218538