Fix invalid link (#12667)

Current link is https://element.eleme.io/nuxtjs.org instead of https://nuxtjs.org/.

examples/docs/en-US/quickstart.md

@@ -262,7 +262,7 @@ Now you have implemented Vue and Element to your project, and it's time to write
 
 ### Use Nuxt.js
 
-We can also start a project using [Nuxt.js](nuxtjs.org):
+We can also start a project using [Nuxt.js](https://nuxtjs.org/):
 
 <div class="glitch-embed-wrap" style="height: 420px; width: 100%;">
   <iframe src="https://glitch.com/embed/#!/embed/nuxt-with-element?path=nuxt.config.js&previewSize=0&attributionHidden=true" alt="nuxt-with-element on glitch" style="height: 100%; width: 100%; border: 0;"></iframe>