made a resolver test case more tolerante.

Author: agentzh

t/023-rewrite/tcp-socket.t

@@ -446,7 +446,7 @@ attempt to send data on a closed socket
 --- request
 GET /t
 --- response_body_like
-^failed to connect: blah-blah-not-found\.agentzh\.org could not be resolved(?: \(\d+: Operation timed out\))?
+^failed to connect: blah-blah-not-found\.agentzh\.org could not be resolved(?: \(\d+: (?:Operation timed out|Host not found)\))?
 connected: nil
 failed to send request: closed$
 --- error_log