Fix Link

[/docs/.../service#proxy-mode-iptables](https://kubernetes.io/docs/concepts/services-networking/service/#proxy-mode-iptables) no longer links to an anchored section of the `service` documentation page. Corrected the link.

Author: kevarr

content/en/docs/tutorials/services/source-ip.md

@@ -74,7 +74,7 @@ deployment.apps/source-ip-app created
 
 Packets sent to ClusterIP from within the cluster are never source NAT'd if
 you're running kube-proxy in
-[iptables mode](/docs/concepts/services-networking/service/#proxy-mode-iptables),
+[iptables mode](/docs/reference/networking/virtual-ips/#proxy-mode-iptables),
 (the default). You can query the kube-proxy mode by fetching
 `http://localhost:10249/proxyMode` on the node where kube-proxy is running.