Add support of secret based AuthN/Z for Route53

[jkremser]

The preferred mechanism of AuthN,Z for aws comm from k8s cluster is using the service account -> role mapping, however in non-managed k8s (no EKS) environments where people just use pure AWS's EC2 instances with kubeadm or using cluster-api (non EKS mode), there the irsa controller (or how is it called today) is missing.

So it would be nice to have a way to make k8gb work also w/o setting this up. Another use-case for this would be a multi-cluster setup where all clusters need to talk to route53, we can't assume the irsa controller in GCP or in Azure.

it's one of the documented ways for externaldns - docs

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[ytsarev]

LGTM, @jkremser I assume you tested it e2e :)

[k0da]

@jkremser just playing with IAM Roles Anywhere. I had to use similar approach across various projects. It was done by extraVolumes and extraVolumeMounts. Would it be better to just allow user to directly specify volume and volumeMounts?