refactor(ligatures): test for harfbuzz feature

A `harfbuzz` feature was introduced in 3e81655.

Ref: 3e81655b0e

modules/ui/ligatures/config.el

@@ -166,8 +166,8 @@ and cannot run in."
  ;; leave the check here for safety.
  ((and (> emacs-major-version 27)
        (or (featurep 'ns)
-           (string-match-p "HARFBUZZ" system-configuration-features))
-       (featurep 'composite))           ; Emacs loads `composite' at startup
+           (featurep 'harfbuzz))
+       (featurep 'composite))   ; Emacs loads `composite' at startup
 
   (use-package! ligature
     :config