test: Use Endpoint instead of EndpointSlice in 1.17
test: Use Endpoint instead of EndpointSlice in 1.17

GKE keeps EndpointSlice controller disabled by default on 1.17 clusters.
This change causes tests to use `Endpoint` object instead of
`EndpointSlice` on 1.17 clusters.

Signed-off-by: Maciej Kwiek <33c1fdf481c8e628d4c6db7ea8dc77f49f2fa5d7@isovalent.com>

tgraf/cilium,tgraf/cilium,tklauser/cilium,tklauser/cilium,tgraf/cilium,michi-covalent/cilium,tgraf/cilium,tgraf/cilium,michi-covalent/cilium,tgraf/cilium,cilium/cilium,tklauser/cilium,michi-covalent/cilium,cilium/cilium,cilium/cilium,tklauser/cilium,tklauser/cilium,michi-covalent/cilium,cilium/cilium,michi-covalent/cilium,cilium/cilium