git not available in operator docker image

[aborilov]

we are using overlays to set some istio configuration, but we can use such kustomization

apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
resources:
- github.com/kubeflow/manifests/istio/istio-install/base?ref=master
patchesStrategicMerge:
- istio-ingressgateway-service.yaml

because operator docker image does not include git in it

2020/12/08 10:43:02 no 'git' program on path: exec: "git": executable file not found in $PATH