modify index.html 2956 problem url address

Author: sozcy

index.html

@@ -62,7 +62,7 @@ <h3>
             <td>Hashset</td>
             <td>
                 <a href="https://leetcode.com/problems/find-common-elements-between-two-arrays/description/">leetcode</a>
-                <a href="https://github.com/sozcy/leetcode_problems/blob/master/2956-找到两个数组中的公共元素[简单]/2956-找到两个数组中的公共元素[简单].md">github</a>
+                <a href="https://github.com/sozcy/leetcode_problems/blob/master/2956-find-common-elements-between-two-arrays/2956-find-common-elements-between-two-arrays.md">github</a>
             </td>
         </tr>