Update Rachel's Name (d2l-ai#669)

* Update Rachel's Name

* Update frontpage.html

static/frontpage/frontpage.html

@@ -281,7 +281,7 @@ <h3><a href="https://www.linkedin.com/in/brent-werness-1506471b7/">布伦特 沃
   <div class = "mdl-cell mdl-cell--3-col mdl-cell--top">
     <div class="author-item">
       <img src="./_images/rachel.jpeg"/>
-      <h3><a href="https://www.linkedin.com/in/rachelsonghu/">胡嵩</a></h3>
+      <h3><a href="https://www.linkedin.com/in/rachelsonghu/">瑞潮儿·胡</a></h3>
       <p> 亚马逊科学家<br><i><a href="http://d2l.ai/chapter_appendix-mathematics-for-deep-learning/index.html">深度学习的数学</a></i></p>
     </div>
   </div>
@@ -334,7 +334,7 @@ <h3><a href="https://github.com/xiaotinghe">何孝霆</a></h3>
   <div class = "mdl-cell mdl-cell--3-col mdl-cell--top">
     <div class="author-item">
       <img src="./_images/rachel.jpeg"/>
-      <h3><a href="https://www.linkedin.com/in/rachelsonghu/">胡嵩</a></h3>
+      <h3><a href="https://www.linkedin.com/in/rachelsonghu/">瑞潮儿·胡</a></h3>
       <p>亚马逊科学家</p>
     </div>
   </div>