update zh-cn/application-dev/reference/apis/js-apis-system-cipher.md.

Signed-off-by: N王永忠 <wangyongzhong2@huawei.com>

zh-cn/application-dev/reference/apis/js-apis-system-cipher.md

@@ -165,7 +165,6 @@ export default {
          console.log(`operation complete!`);
         }
      });        
-    });    
   }
 }