i18n: use the right parentheses

examples/docs/en-US/i18n.md

@@ -43,14 +43,14 @@ Currently Element ships with the following languages:
   <li>English (en)</li>
   <li>German (de)</li>
   <li>Portuguese (pt)</li>
-  <li>Spanish（es）</li>
-  <li>Danish（da）</li>
-  <li>French（fr）</li>
-  <li>Norwegian（nb-NO）</li>
-  <li>Traditional Chinese（zh-TW）</li>
-  <li>Italian（it）</li>
-  <li>Korean（ko）</li>
-  <li>Japanese（ja）</li>
+  <li>Spanish (es)</li>
+  <li>Danish (da)</li>
+  <li>French (fr)</li>
+  <li>Norwegian (nb-NO)</li>
+  <li>Traditional Chinese (zh-TW)</li>
+  <li>Italian (it)</li>
+  <li>Korean (ko)</li>
+  <li>Japanese (ja)</li>
 </ul>
 
 If your target language is not included, you are more than welcome to contribute: just add another language config [here](https://github.com/ElemeFE/element/tree/master/src/locale/lang) and create a pull request.