tests: use different website for ecore_test_ecore_file_download

Summary:
while it may be the case that we do not control example.com, it is also
the case that loading anything from enlightenment.org takes 10+ seconds
longer (at minimum) than loading example.com

ref T6853
Depends on D5884

Reviewers: stefan_schmidt

Subscribers: cedric

Maniphest Tasks: T6853

Differential Revision: https://phab.enlightenment.org/D5885