docs: update ref attribute example * docs: update ref attribute example ref -> useTemplateRef * fix: add import of useTemplateRef. https://github.com/vuejs/docs/pull/2991#discussion_r1742971516 (#1423)

docs: update ref attribute example * docs: update ref attribute example ref -> useTemplateRef * fix: add import of useTemplateRef. https://github.com/vuejs/docs/pull/2991#discussion_r1742971516 (#1423) #1417