优化部分代码,尝试修复热键回调多次bug

Constant/UpdateType.cs

@@ -0,0 +1,17 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+/// <summary>
+/// 更新源
+/// </summary>
+namespace GeekDesk.Constant
+{
+    public enum UpdateType
+    {
+        Gitee = 1,
+        GitHub = 2
+    }
+}