[kde-plasma] use breath-dark LnF package

Plasma 5.24 seems to have changed how they load the default theme,
so now it loads a Light mode theme by default.

Select the Breath Dark Look And Feel package by default.

Signed-off-by: Dan Johansen <strit@manjaro.org>

overlays/kde-plasma/etc/xdg/kdeglobals

@@ -121,6 +121,7 @@ widgetStyle=Breeze
 Theme=breeze-dark
 
 [KDE]
+LookAndFeelPackage=org.manjaro.breath-dark.desktop
 AnimationDurationFactor=0.5
 ColorScheme=Breeze
 DoubleClickInterval=400