Adds deref call in assertion for hickory-client README example (#2173)

* Adds deref call in assertion

* Adds inner struct to pattern match

---------

Co-authored-by: Benjamin Fry <benjaminfry@me.com>

crates/client/README.md

@@ -27,7 +27,7 @@ use std::str::FromStr;
 use hickory_client::client::{Client, SyncClient};
 use hickory_client::udp::UdpClientConnection;
 use hickory_client::op::DnsResponse;
-use hickory_client::rr::{DNSClass, Name, RData, Record, RecordType};
+use hickory_client::rr::{rdata::A, DNSClass, Name, RData, Record, RecordType};
 
 let address = "8.8.8.8:53".parse().unwrap();
 let conn = UdpClientConnection::new(address).unwrap();
@@ -49,7 +49,7 @@ let answers: &[Record] = response.answers();
 // Records are generic objects which can contain any data.
 //  In order to access it we need to first check what type of record it is
 //  In this case we are interested in A, IPv4 address
-if let Some(RData::A(ref ip)) = answers[0].data() {
+if let Some(RData::A(A(ref ip))) = answers[0].data() {
     assert_eq!(*ip, Ipv4Addr::new(93, 184, 215, 14))
 } else {
     assert!(false, "unexpected result")