envoy: Avoid having duplicated backend service
envoy: Avoid having duplicated backend service

The same backend service can be used multiple times in different rules
(e.g. with different host values), which leads to failure in envoy config
due to multiple Cluster resources with same name. Hence, de-dup should be
done.

This is identified as part of conformance test.

Signed-off-by: Tam Mach <2524536bcff1dac29d2f6b38b02eb7c94efb5019@isovalent.com>

michi-covalent/cilium,cilium/cilium,cilium/cilium,michi-covalent/cilium,michi-covalent/cilium,cilium/cilium,cilium/cilium,michi-covalent/cilium,michi-covalent/cilium,cilium/cilium