add missing code element around important style

Author: chrisvfritz

src/guide/migration.md

@@ -575,7 +575,7 @@ If you really need to override another `!important`, you must use the string syn
 {% raw %}
 <div class="upgrade-path">
   <h4>Upgrade Path</h4>
-  <p>Run the <a href="https://github.com/vuejs/vue-migration-helper">migration helper</a> on your codebase to find examples of style bindings with `!important` in objects.</p>
+  <p>Run the <a href="https://github.com/vuejs/vue-migration-helper">migration helper</a> on your codebase to find examples of style bindings with <code>!important</code> in objects.</p>
 </div>
 {% endraw %}