pamtest: Use QStringLiteral
It's needed because the explicit 'set(KDE_COMPILERSETTINGS_LEVEL "5.82")' has been dropped in 47528d64 and falling back to the (higher) minimum required ecm version now, -DQT_NO_CAST_FROM_ASCII is pulled in.
It's needed because the explicit 'set(KDE_COMPILERSETTINGS_LEVEL "5.82")' has been dropped in 47528d64 and falling back to the (higher) minimum required ecm version now, -DQT_NO_CAST_FROM_ASCII is pulled in.