Show clusterIP in Services diagrams instead of ServiceIP (#10663)

* Use clusterIP instead of ServiceIP in graphs and documentation

Using ServiceIP instead of clusterIP in images can be confusing when
they're showing the clusterIP.

Since the SVGs are updated, the "Note" is now redundant.

* Update out-dated service diagram PNGs

content/en/docs/concepts/services-networking/service.md

@@ -173,8 +173,6 @@ By default, the choice of backend is round robin.
 
 ![Services overview diagram for userspace proxy](/images/docs/services-userspace-overview.svg)
 
-Note that in the above diagram, `clusterIP` is shown as `ServiceIP`.
-
 ### Proxy-mode: iptables
 
 In this mode, kube-proxy watches the Kubernetes master for the addition and
@@ -192,8 +190,6 @@ having working [readiness probes](/docs/tasks/configure-pod-container/configure-
 
 ![Services overview diagram for iptables proxy](/images/docs/services-iptables-overview.svg)
 
-Note that in the above diagram, `clusterIP` is shown as `ServiceIP`.
-
 ### Proxy-mode: ipvs
 
 {{< feature-state for_k8s_version="v1.9" state="beta" >}}