applets/batterymonitor: Use the same property to define hasBatteries

Otherwise it looks weird when it gets out of sync because Has
Cumulative.

BUG: 448797
FIXED-IN: 5.24

applets/batterymonitor/package/contents/ui/CompactRepresentation.qml

@@ -19,7 +19,7 @@ MouseArea {
     readonly property bool isConstrained: plasmoid.formFactor === PlasmaCore.Types.Vertical || plasmoid.formFactor === PlasmaCore.Types.Horizontal
     property real brightnessError: 0
     property QtObject batteries
-    property bool hasBatteries: batteries.count > 0
+    property bool hasBatteries: false
 
     hoverEnabled: true
 

applets/batterymonitor/package/contents/ui/main.qml

@@ -198,6 +198,7 @@ Item {
     }
 
     Plasmoid.compactRepresentation: CompactRepresentation {
+        hasBatteries: batterymonitor.hasBatteries
         batteries: batterymonitor.batteries
 
         onWheel: {