Use syntax quote for `defnc` in `defnc-`

[ferdinand-beyer]

Otherwise defnc will not resolve when users only refer defnc-.

Consider the following example:

(ns example.core
  (:require ["react" :as react]
            ["react-dom" :as react-dom]
            [helix.core :refer [$ defnc-]]))

(defnc- my-component []
  ($ "h1" "Hello, World!"))

(defn render []
  (react-dom/render ($ my-component) (.getElementById js/document "app")))

Currently, this will fail to compile since the defnc- macro expands to defnc which is not defined in this context.