global-functions: $CertificateDownload: add a delay

For any reason the imported certificate(s) is/are not available for
fetch command immediately. Let's add a delay here... It should not hurt
as certificates are not imported that often.

global-functions.rsc

@@ -137,6 +137,7 @@
         "CommonName \"" . $CommonName . "\"!") false;
     :return false;
   }
+  :delay 1s;
   :return true;
 }