[Readme] Fix Readme image alignment

Author: IIzzaya

README-ZH.md

@@ -228,9 +228,9 @@ UIWidgets支持渲染文本中包含的表情。表情的图片来自[https://ww
 
 #### 十一、与GameObject进行拖拽交互
 
-<div style="text-align: center">
+<p align="center">
   <img src="https://connect-prd-cdn.unity.com/20190718/p/images/e3c9cf9b-c732-4eb2-9afd-fe7de894f342_Custom_Inspector_Showcase_320px.gif" width="300"/>
-</div>
+</p>
 
 我们提供了一个包装好的`UnityObjectDetector`组件以及`onRelease`回调函数，借此您可以实现简单地将物体（例如Hierarchy内的场景物体、Project窗口下的文件等）拖拽至区域内，来获得`UnityEngine.Object[] `类型的引用并进行操作。
 

README.md

@@ -267,9 +267,9 @@ in the texture `rowCount`, and number of columns `colCount`.
 
 #### Interact with GameObject Drag&Drops
 
-<div style="text-align: center">
+<p align="center">
   <img src="https://connect-prd-cdn.unity.com/20190718/p/images/e3c9cf9b-c732-4eb2-9afd-fe7de894f342_Custom_Inspector_Showcase_320px.gif" width="300"/>
-</div>
+</p>
 
 With the provided packaged stateful widget `UnityObjectDetector` and its `onRelease` callback function, you can easily drag some objects (for example GameObject from Hierarchy, files from Project Window, etc) into the area, get the UnityEngine.Object[] references and make further modification.