Fix carousel not moving issues

Author: Yiyiyimu

content/zh/docs/tutorials/kubernetes-basics/update/update-intro.html

@@ -97,19 +97,19 @@ <h2 style="color: #3771e3;">滚动更新概述</h2>
                         <li data-target="#myCarousel" data-slide-to="3"></li>
                     </ol>
                       <div class="carousel-inner" role="listbox">
-                        <div class="item active">
+                        <div class="item carousel-item active">
                           <img src="/docs/tutorials/kubernetes-basics/public/images/module_06_rollingupdates1.svg" >
                         </div>
 
-                        <div class="item">
+                        <div class="item carousel-item">
                           <img src="/docs/tutorials/kubernetes-basics/public/images/module_06_rollingupdates2.svg">
                         </div>
 
-                        <div class="item">
+                        <div class="item carousel-item">
                           <img src="/docs/tutorials/kubernetes-basics/public/images/module_06_rollingupdates3.svg">
                         </div>
 
-                        <div class="item">
+                        <div class="item carousel-item">
                           <img src="/docs/tutorials/kubernetes-basics/public/images/module_06_rollingupdates4.svg">
                         </div>
                       </div>