Improve release process to ensure we have stable & consistent format (mediaType)

### What would you like to be added?

I checked several etcd released images, different images may have different mediaType. I think the reason could be different release persons have different docker versions. FYI. etcd has a [release process](https://github.com/etcd-io/etcd/blob/main/Documentation/contributor-guide/release.md), but release persons use their local env to build/release etcd.

In the long run, we should improve our release process to ensure we have stable & expected images. cc @ivanvc @joshjms

Not sure how Kubernetes release team generate the images?

```
3.6.0 application/vnd.docker.distribution.manifest.list.v2+json
3.6.1 application/vnd.docker.distribution.manifest.list.v2+json
3.6.2 application/vnd.oci.image.index.v1+json
3.6.3 application/vnd.oci.image.manifest.v1+json
3.6.4 application/vnd.docker.distribution.manifest.v2+json
3.6.5 application/vnd.docker.distribution.manifest.list.v2+json
3.6.6 application/vnd.oci.image.manifest.v1+json

3.5.22 application/vnd.oci.image.index.v1+json
3.5.23 application/vnd.docker.distribution.manifest.list.v2+json
3.5.24 application/vnd.docker.distribution.manifest.list.v2+json
3.5.25 application/vnd.oci.image.index.v1+json
```

Note it's breaking Kubeadm test case, refer to https://github.com/kubernetes/kubernetes/issues/135697

References:
- https://github.com/kubernetes/kubernetes/issues/121742
- https://docs.docker.com/build/exporters/#oci-media-types

### Why is this needed?

.