etcd on Kubernetes quick install script doesn't work on Kubernetes 1.20

[bvankampen]

The quick install script https://docs.ondat.io/sh/deploy-etcd.sh for etcd on Kubenetes found on https://docs.ondat.io/docs/prerequisites/etcd/ doesn't work on Kubernetes 1.20 because of the deprecation of the annotation "service.alpha.kubernetes.io/tolerate-unready-endpoints: "true" (replaces by the spec publishNotReadyAddresses: true) in the etcd service definition.