remove unused title for Custom Renderer (#2252)

Author: tlagoda

.vitepress/config.ts

@@ -318,7 +318,6 @@ export const sidebar: ThemeConfig['sidebar'] = {
         //   text: 'Building a Library for Vue',
         //   link: '/guide/extras/building-a-library'
         // },
-        // { text: 'Custom Renderers', link: '/guide/extras/custom-renderer' },
         // {
         //   text: 'Vue for React Devs',
         //   link: '/guide/extras/vue-for-react-devs'