Remove debug println from computePrefHeight method

Debugging output was mistakenly left in the computePrefHeight method. This commit removes the unnecessary println statement to clean up the code and avoid unwanted console output.

gemsfx/src/main/java/com/dlsc/gemsfx/skins/PagingListViewSkin.java

@@ -130,7 +130,6 @@ private Node wrapInScrollPane(Node node) {
 
     @Override
     protected double computePrefHeight(double width, double topInset, double rightInset, double bottomInset, double leftInset) {
-        System.out.println("w: " + width);
         return stackPane.prefHeight(width) + topInset + bottomInset;
     }