fix: update images path

Author: yanglbme

solution/0400-0499/0463.Island Perimeter/README.md

@@ -24,9 +24,9 @@
 
 <strong>解释:</strong> 它的周长是下面图片中的 16 个黄色的边：
 
-<img src="https://assets.leetcode-cn.com/aliyun-lc-upload/uploads/2018/10/12/island.png">
 </pre>
 
+![](./images/island.png)
 
 
 ## 解法

solution/0400-0499/0463.Island Perimeter/README_EN.md

@@ -43,13 +43,9 @@
 
 <strong>Explanation:</strong> The perimeter is the 16 yellow stripes in the image below:
 
-
-
-<img src="https://assets.leetcode.com/uploads/2018/10/12/island.png" style="width: 221px; height: 213px;" />
-
 </pre>
 
-
+![](./images/island.png)
 
 
 ## Solutions