OSX/CI: kde-baseapps fails to build on branch frameworks

["Marko Käning"]

Hi Kevin,

> Note: That needs Qt 5.4 -- QSignalSpy can take a PMF only since that.

I guess that test's code should then be guarded appropriately, so that it
builds also on KDE CI's still being used Qt 5.3.2, right?

Greets,
Marko