Update endpoint slices docs

Be more explicit on the "duplicate endpoints" sections about what are the consumers expectations and the need to parse all the list of slices and remove only the duplicates

Author: aojea

content/en/docs/concepts/services-networking/endpoint-slices.md

@@ -233,11 +233,12 @@ different EndpointSlice objects can arrive at the Kubernetes client watch / cach
 at different times.
 
 {{< note >}}
-Clients of the EndpointSlice API must be able to handle the situation where
-a particular endpoint address appears in more than one slice.
+Clients of the EndpointSlice API must iterate through all the existing EndpointSlices
+associated to a Service and build a complete list of unique network endpoints. It is
+important to mention that endpoints may be duplicated in different EndointSlices.
 
-You can find a reference implementation for how to perform this endpoint deduplication
-as part of the `EndpointSliceCache` code within `kube-proxy`.
+You can find a reference implementation for how to perform this endpoint aggregation
+and deduplication as part of the `EndpointSliceCache` code within `kube-proxy`.
 {{< /note >}}
 
 ## Comparison with Endpoints {#motivation}