Fix #496, Rate app link in overflow menu

The test is very minimalistic for a few reasons. On the emulator, there
is no Play Store App, on a device there probably is, but clicking the
menu would then leave Catroid. This would cause us to lose control over
the test, because we're not in Catroid anymore.
Merge pull request #539 from Catrobat/EvaluateAppLink#496

Fix #496, Rate app link in overflow menu