change sending timeout

src/MailKitMailModule.cs

@@ -256,7 +256,7 @@ namespace OpenSim.Modules.EMail
             using (var client = new SmtpClient())
             {
                 client.CheckCertificateRevocation = false;
-                client.Timeout = 10;
+                client.Timeout = 10000;
 
                 if (SMTP_SERVER_SSL == true)
                 {