Skip test -e command
Summary: See above. Fails on unix systems since cmake replaces -e by -E.
Test Plan: No test needed. If it builds, everything is fine.
Reviewers: O1 MITK Core, kislinsk
Reviewed By: O1 MITK Core, kislinsk
Maniphest Tasks: T26252
Differential Revision: https://phabricator.mitk.org/D193