convert bootstrap image to multi-arch image

[upodroid]

Part of #31273

/cc @dims @BenTheElder

I built this image successfully in the ii-sandbox project.

https://console.cloud.google.com/cloud-build/builds;region=global/4579d4ed-c523-4f3b-8344-1d60b82c482b;step=1?project=k8s-infra-ii-sandbox

Took 45 minutes to build :(

 mahamed  REDACTED  ~  $  gcrane manifest gcr.io/k8s-infra-ii-sandbox/bootstrap:v20231120-ad4f76d838-dirty
{
  "schemaVersion": 2,
  "mediaType": "application/vnd.oci.image.index.v1+json",
  "manifests": [
    {
      "mediaType": "application/vnd.oci.image.manifest.v1+json",
      "digest": "sha256:72eee01f4d5bdd5464aac0346cc70c4a76fc13f0b83aa49b288d92f11a4b498a",
      "size": 2956,
      "platform": {
        "architecture": "amd64",
        "os": "linux"
      }
    },
    {
      "mediaType": "application/vnd.oci.image.manifest.v1+json",
      "digest": "sha256:167cdc138e1cb3c90f5d25a12faaedbce39b176410326b83f507d7fb38e71cd0",
      "size": 2956,
      "platform": {
        "architecture": "arm64",
        "os": "linux"
      }
    },
    {
      "mediaType": "application/vnd.oci.image.manifest.v1+json",
      "digest": "sha256:de1782cd1effda6c2386573b103ccd52bd0b22adfe6e7a3084e37047ce275ef3",
      "size": 566,
      "annotations": {
        "vnd.docker.reference.digest": "sha256:72eee01f4d5bdd5464aac0346cc70c4a76fc13f0b83aa49b288d92f11a4b498a",
        "vnd.docker.reference.type": "attestation-manifest"
      },
      "platform": {
        "architecture": "unknown",
        "os": "unknown"
      }
    },
    {
      "mediaType": "application/vnd.oci.image.manifest.v1+json",
      "digest": "sha256:e3d02f5dc6794c7cae3b72e248fe4fdbf554a4324621a91a16e896477b11871e",
      "size": 566,
      "annotations": {
        "vnd.docker.reference.digest": "sha256:167cdc138e1cb3c90f5d25a12faaedbce39b176410326b83f507d7fb38e71cd0",
        "vnd.docker.reference.type": "attestation-manifest"
      },
      "platform": {
        "architecture": "unknown",
        "os": "unknown"
      }
    }
  ]
}

[k8s-ci-robot]

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[upodroid]

Replaced with kubekins-e2e v2 image instead