release-1.2: Helm chart 2.0.0 with changelog

[wongma7]

Is this a bug fix or adding new feature? new chart release

What is this PR about? / Why do we need it? releases chart 2.0.0 currently sitting in master branch. #406

What testing is done?
Install the existing chart 1.2.4 and try dynamic provisioning example
helm repo add aws-efs-csi-driver https://kubernetes-sigs.github.io/aws-efs-csi-driver/
helm repo update
helm upgrade --install aws-efs-csi-driver --namespace kube-system aws-efs-csi-driver/aws-efs-csi-driver
k apply -f ./examples/kubernetes/dynamic_provisioning/specs/
k exec -it efs-app -- cat /data/out

Upgrade to 2.0.0 (obviously this won't work if I set values that existed in old chart that were moved in new chart, hence major version got bumped from 1 to 2). and check example still works
helm upgrade --install aws-efs-csi-driver ./charts/aws-efs-csi-driver -n kube-system
k exec -it efs-app -- cat /data/out

Delete and recreate example and check it still works.
k delete -f ./examples/kubernetes/dynamic_provisioning/specs/
k apply -f ./examples/kubernetes/dynamic_provisioning/specs/
k exec -it efs-app -- cat /data/out

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: wongma7

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[kbasv]

/lgtm