修复get请求，参数获取问题

Filters/AuthorizationFilter.cs

@@ -136,6 +136,7 @@ namespace Filters
 
         public string GetParam(string content, string key)
         {
+            if(content.StartsWith("?")) content = content.Substring(1);
             string[] data = content.Split('&');
             foreach(string sub in data)
             {