Add stuvus.uni-stuttgart.de to HSTS preload list

Change-Id: If7ff9c7f878374335c779456e88c1314005d9f12
Reviewed-on: https://chromium-review.googlesource.com/924684


Reviewed-by: Eric Lawrence <elawrence@chromium.org>
Commit-Queue: Nick Harper <nharper@chromium.org>
Cr-Commit-Position: refs/heads/master@{#537927}