✨ AWSCluster: Allow setting ImageLookupOrg at the cluster level

[alexbrand]

What this PR does / why we need it:

This PR adds a new field, ImageLookupOrg, to the AWSClusterSpec struct. The ImageLookupOrg field can be used to override the organization ID used when looking up AMIs for machines. Note that the ImageLookupOrg is only used when a machine does not specify an AMI ID.

With this change, the ImageLookupOrg can be set at the cluster-level or at the machine-level. The machine-level ImageLookupOrg takes precedence over the cluster-level ImageLookupOrg.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #1292

[k8s-ci-robot]

Hi @alexbrand. Thanks for your PR.

I'm waiting for a kubernetes-sigs member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

I understand the commands that are listed here.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[detiber]

/ok-to-test
/lgtm

[alexbrand]

@detiber I noticed that the CRD yaml got restructured a bit in this PR. Is that expected?

[detiber]

@detiber I noticed that the CRD yaml got restructured a bit in this PR. Is that expected?

Yes, this is the first divergence that I'm aware of with v1alpha2 -> v1alpha3, so this is expected :)

[alexbrand]

Got it! Thanks @detiber

[detiber]

/assign @ncdc

[detiber]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: alexbrand, detiber

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [detiber]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment