Use our DNS canary in the test suite

Closes #3237

bin/varnishtest/tests/v00016.vtc

@@ -85,7 +85,7 @@ varnish v1 -errvcl {Regexp compilation error:} {
 varnish v1 -errvcl {resolves to too many addresses} {
 	backend b { .host = "127.0.0.1"; }
 	sub vcl_recv {
-		if (remote.ip == "fastly.com") {}
+		if (remote.ip == "dns-canary-multi.varnish-cache.org") {}
 	}
 }
 

bin/varnishtest/vtc_misc.c

@@ -354,21 +354,21 @@ dns_works(void)
 	char abuf[VTCP_ADDRBUFSIZE];
 	char pbuf[VTCP_PORTBUFSIZE];
 
-	sa = VSS_ResolveOne(NULL, "varnish.org", NULL,
+	sa = VSS_ResolveOne(NULL, "dns-canary.varnish-cache.org", NULL,
 	    AF_INET, SOCK_STREAM, 0);
 	if (sa == NULL)
 		return (0);
 	VTCP_name(sa, abuf, sizeof abuf, pbuf, sizeof pbuf);
 	free(sa);
-	if (strcmp(abuf, "176.58.90.154"))
+	if (strcmp(abuf, "192.0.2.255"))
 		return (0);
 
-	sa = VSS_ResolveOne(NULL, "varnish.org", NULL,
+	sa = VSS_ResolveOne(NULL, "dns-canary.varnish-cache.org", NULL,
 	    AF_INET6, SOCK_STREAM, 0);
 	if (sa == NULL)
-		return (0);
+		return (1); /* the canary is ipv4 only */
 	free(sa);
-	return (1);
+	return (0);
 }
 
 /* SECTION: feature feature