Moved tests from browsertests repository to WikiLove repository

See also commits in browsertests[1] and WikiLove[2] repositories.

1: https://gerrit.wikimedia.org/r/#/c/113101/
2: https://gerrit.wikimedia.org/r/#/c/113104/

Bug: 61135
Change-Id: I0371d050e033641b1e0e173808390227c9331014