Set correct license link location in E2E test

* Remove login since it's not longer needed
* Point to a new smaller test page instead of Lightbox_demo
 which should make the tests run much faster
* Tweak selenium scroll workaround which seems to be speed-dependant

Change-Id: I247ae6a5044ecc93b6f3839f1b9ed955b488b5a7
Mingle: https://wikimedia.mingle.thoughtworks.com/projects/multimedia/cards/475
Merge "Set correct license link location in E2E test"