✨ Cancel instance refresh on any relevant change to ASG instead of blocking until previous one is finished (which may have led to failing nodes due to outdated join token)

[AndiDog]

What type of PR is this?

/kind feature

What this PR does / why we need it:

Changing any relevant spec.* for an AWSMachinePool triggers rolling of nodes via ASG instance refresh. If another change happens shortly afterwards, it has to wait until the first rollout is done, and will then trigger another instance refresh. But it is neither necessary nor desired to roll all worker nodes twice in such a case, and it's much slower. Instead, cancel the one pending instance refresh, wait until another one can be started, and apply the latest change as soon as possible with the second instance refresh.

This change has been running fine in Giant Swarm's CAPA fork for three months at the time of opening this PR.

Special notes for your reviewer:

This PR stacks on top of #5148, so let's please review and merge that other PR first. After that's done, this PR can be retargeted to main. I didn't want to separate these independent changes because otherwise I have to deal with merge conflicts.

Checklist:

• squashed commits
• includes documentation
• includes emojis
• adds unit tests
• adds or updates e2e tests

Release note:

Cancel instance refresh on any relevant change to ASG instead of blocking until previous one is finished

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by:
Once this PR has been reviewed and has the lgtm label, please ask for approval from andidog. For more information see the Kubernetes Code Review Process.

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

Needs approval from an approver in each of these files:

• OWNERS

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

[richardcase]

For reviewers this now stack on #5172 and not #5148.