Clarify QtQuick dependency
There is no "Qt Quick plugin" in the source as far as I can see. QtQuick is only used in tests.
Make the dependency conditional on BUILD_TESTING and fix the misleading cmake output.
There is no "Qt Quick plugin" in the source as far as I can see. QtQuick is only used in tests.
Make the dependency conditional on BUILD_TESTING and fix the misleading cmake output.