replace symlink hack with QFINDTESTDATA
Summary:
the latter encapsulates very smart logic to find test fixtures which works
just about all the time
Test Plan:
- master passes test
- remove symlink link
- fails to pass
- use diff with qfindtestdata
- passes again
Reviewers: Plasma, davidedmundson
Reviewed By: Plasma, davidedmundson
Subscribers: plasma-devel
Tags: Plasma
Differential Revision: https://phabricator.kde.org/D22134