DOC-3147: Remove CSS classes section and related file for split buttons

Author: ArvinJ-H

modules/ROOT/pages/custom-split-toolbar-button.adoc

@@ -55,8 +55,4 @@ The `+fetch+` function is called whenever the split button's drop-down menu is o
 
 include::partial$components/choice-menu-items.adoc[]
 
-== CSS Classes
-
-include::partial$components/split-button-css-classes.adoc[]
-
 include::partial$misc/onSetup.adoc[]