slapos_jio_ui_test: Added test for service worker

  It was added as "0" in order to run first, as the later tests calls logout and can be started as anonymous.
3 jobs for master in 0 seconds
Status Job ID Name Coverage
  External
failed SlapOS-Master.UnitTest-Rafael

01:48:39

failed SlapOS.Eggs.UnitTest-Rafael.Python2

00:28:41

failed SlapOS-Master.UnitTest-Rafael

01:28:07