Use 4.dp spacing for checklist items.

David (UX) changed the spec (to revert the 16.dp added in previous commit - and prefers 4.dp for now).

Author: shamalip

samples/user-interface/appwidgets/src/main/java/com/example/platform/ui/appwidgets/glance/layout/collections/layout/CheckListLayout.kt

@@ -401,7 +401,7 @@ private object CheckListLayoutTextStyles {
 private object CheckListLayoutDimensions {
   val widgetPadding = 12.dp
 
-  val verticalItemSpacing = 16.dp
+  val verticalItemSpacing = 4.dp
 
   // Full width scrollable content
   val scaffoldHorizontalPadding = 0.dp