Moved tests to UploadWizard repository

See also the commit[1] in UploadWizard repository that moves the tests there and the commit[2] in mediawiki/selenium repository that documents changes in Jenkins jobs.

1: https://gerrit.wikimedia.org/r/#/c/112895/
2: https://gerrit.wikimedia.org/r/#/c/112899/

Bug: 56419
Change-Id: I3f53483791a5e6427a5e8348ccc5a346c0cb60b7