Changed another nonexistent host name to be under the haxx.se domain

to guarantee against it ever being valid.

tests/data/test20

@@ -23,7 +23,7 @@ http
 attempt connect to non-existing host name
  </name>
  <command>
-non-existing-and-weeeeeeirdname.
+non-existing-host.haxx.se.
 </command>
 </client>