docs: Added links to french translation (#401)

* added links to french translation

* removed useless whitespaces

docs/readme_cn.md

@@ -34,7 +34,7 @@
     <a href="https://github.com/anuraghazra/github-readme-stats/issues/new/choose">请求增加功能</a>
   </p>
   <p align="center">
-    <a href="/docs/readme_fr.md">Français </a>
+    <a href="/docs/readme_fr.md">Français</a>
     ·
     <a href="/docs/readme_cn.md">简体中文</a>
     ·