fix main empty list error

Author: yangxuilyx

src/c#/GeneralUpdate.ClientCore/GeneralClientBootstrap.cs

@@ -171,7 +171,7 @@ private async Task ExecuteWorkflowAsync()
             BlackListManager.Instance?.AddBlackFiles(_configInfo.BlackFiles);
             BlackListManager.Instance?.AddBlackFileFormats(_configInfo.BlackFormats);
             BlackListManager.Instance?.AddSkipDirectorys(_configInfo.SkipDirectorys);
-            
+
             _configInfo.Encoding = GetOption(UpdateOption.Encoding) ?? Encoding.Default;
             _configInfo.Format = GetOption(UpdateOption.Format) ?? Format.ZIP;
             _configInfo.DownloadTimeOut = GetOption(UpdateOption.DownloadTimeOut) == 0
@@ -185,7 +185,7 @@ private async Task ExecuteWorkflowAsync()
             if (_configInfo.IsMainUpdate)
             {
                 _configInfo.UpdateVersions = upgradeResp.Body.OrderBy(x => x.ReleaseDate).ToList();
-                _configInfo.LastVersion = _configInfo.UpdateVersions.Last().Version;
+                _configInfo.LastVersion = mainResp.Body.OrderBy(x => x.ReleaseDate).Last().Version;
 
                 var failed = CheckFail(_configInfo.LastVersion);
                 if (failed) return;