LibGUI: Put some more space between check boxes and their label text

Userland/Libraries/LibGUI/CheckBox.cpp

@@ -17,7 +17,7 @@ namespace GUI {
 
 static const int s_box_width = 13;
 static const int s_box_height = 13;
-static const int s_horizontal_padding = 4;
+static const int s_horizontal_padding = 6;
 
 CheckBox::CheckBox(String text)
     : AbstractButton(move(text))