Update README.md

Author: ovadiagal

rust/src/dns_gateway/README.md

@@ -308,7 +308,7 @@ dig two.s3.aws.com
 dig example.com
 
 # Unmatched domain, will defer to external DNS
-dig github.palantir.build
+dig github.com
 
 # Will reach cluster_1
 curl http://s3.aws.com./