fix: Remove unused namespace

Author: jcs090218

Assets/JCSUnity/Editor/JCSUnity_About.cs

@@ -7,9 +7,9 @@
  * $Notice: See LICENSE.txt for modification and distribution information 
  *	                 Copyright (c) 2016 by Shen, Jen-Chieh $
  */
-using UnityEngine;
 using System.Collections.Generic;
 using UnityEditor;
+using UnityEngine;
 
 namespace JCSUnity
 {

Assets/JCSUnity/Editor/JCSUnity_EditortUtil.cs

@@ -7,7 +7,6 @@
  * $Notice: See LICENSE.txt for modification and distribution information 
  *	                 Copyright © 2021 by Shen, Jen-Chieh $
  */
-using System.Xml.Linq;
 using UnityEditor;
 using UnityEngine;