LibWeb: Make node cloning methods const

Author: https://github.com/tcl3
Commit: a467005855
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/3228
Reviewed-by: https://github.com/gmta ✅

Libraries/LibWeb/HTML/HTMLScriptElement.cpp

@@ -651,7 +651,7 @@ void HTMLScriptElement::set_async(bool async)
 }
 
 // https://html.spec.whatwg.org/multipage/scripting.html#script-processing-model:concept-node-clone-ext
-WebIDL::ExceptionOr<void> HTMLScriptElement::cloned(Node& copy, bool subtree)
+WebIDL::ExceptionOr<void> HTMLScriptElement::cloned(Node& copy, bool subtree) const
 {
     TRY(Base::cloned(copy, subtree));