[ExpandableListItem] Fix determination of the number of list items

This fixes the problem of the default list item not being rendered with
bold text as intended, which was caused by checking the count property
of the wrong thing and causing a condition to always evaluate to false.

src/declarativeimports/plasmaextracomponents/qml/ExpandableListItem.qml

@@ -411,7 +411,7 @@ Item {
                         // Even if it's the default item, only make it bold when
                         // there's more than one item in the list, or else there's
                         // only one item and it's bold, which is a little bit weird
-                        font.weight: listItem.isDefault && listItem.ListView.count > 1
+                        font.weight: listItem.isDefault && listItem.ListView.view.count > 1
                                             ? Font.Bold
                                             : Font.Normal
                     }