https://istio.io/latest/docs/reference/config/networking/sidecar/
https://istio.io/latest/docs/reference/glossary/#workload
I am not very sure on how or why to use this...
apiVersion:
networking.istio.io/v1alpha3
kind: Sidecar
metadata:
name: default
namespace: foo
spec:
egress:
- hosts:
- "./*"
- "istio-system/*"