Add reliability values overlay to istio-cni component
What
The change adds a reliability values overlay to the istio-cni component. This means that the istio-cni component will now be able to read values from the reliability-overlay-istio-cni-values-${cluster} ConfigMap.
Why
All the base config for istio should live within the Reliability tenant.
Related Issue: https://gitlab.com/gitlab-com/gl-infra/reliability/-/issues/24157
Edited by Marcel Chacon