Fix duplicates handlers for interfaces that use interfaces

* module/ice-9/boot-9.scm (duplicate-handlers): Use module-variable
instead of module-local-variable in the warn-override-core, first, and
last handlers.  Fixes #47084 mostly, though relative to pre-3.0 there is
still a difference in that a module needs to explicitly declare which
bindings are intended as replacements -- a binding being a replacement
is a property of the module in 3.0, rather than the variable as was the
case before 3.0.

module/ice-9/boot-9.scm

@@ -4152,13 +4152,13 @@ but it fails to load."
                      (module-name module)
                      (module-name int2)
                      name)
-             (module-local-variable int2 name))))
+             (module-variable int2 name))))
 
     (define (first module name int1 val1 int2 val2 var val)
-      (or var (module-local-variable int1 name)))
+      (or var (module-variable int1 name)))
 
     (define (last module name int1 val1 int2 val2 var val)
-      (module-local-variable int2 name))
+      (module-variable int2 name))
 
     (define (noop module name int1 val1 int2 val2 var val)
       #f)