Backport of build.yml: Add ECR images back into release/1.3.x

[hc-github-team-consul-core]

Backport

This PR is auto-generated from #3668 to be assessed for backporting due to the inclusion of the label backport/1.3.x.

🚨

Warning automatic cherry-pick of commits failed. If the first commit failed,
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The person who merged in the original PR is:
@david-yu
This person should manually cherry-pick the original PR into a new backport PR,
and close this one when the manual backport PR is merged in.

merge conflict error: POST https://api.github.com/repos/hashicorp/consul-k8s/merges: 409 Merge conflict []

The below text is copied from the body of the original PR.

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Changes proposed in this PR

Some customers and practitioners would like AWS ECR images due the reduced cost of pulling images onto their EKS clusters. This PR makes puts back the publishing of the k8s images.

• Previous builds were removed by https://github.com/hashicorp/consul-k8s/pull/1364/files
• Closes Publish consul-k8s-control-plane Docker image to ECR #3091

How I've tested this PR

How I expect reviewers to test this PR

Checklist

• Tests added
• CHANGELOG entry added

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Overview of commits

• 8fba327 - 9a73765 - dd2222f - eaf6477

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