[tests] Raise arrow on testmarginbottom higher on z-index. JB#56014 OMP#JOLLA-459
[tests] Raise arrow on testmarginbottom higher on z-index. JB#56014 OMP#JOLLA-459

sailfishos/sailfish-browser,sailfishos/sailfish-browser,sailfishos/sailfish-browser,sailfishos/sailfish-browser,sailfishos/sailfish-browser