Taint nodes for deletion asynchronously

[abdelrahman882]

What type of PR is this?

/kind feature
/kind failing-test
/kind flake

What this PR does / why we need it:

Tainting nodes for deletion requires a remote call which takes time when scaling down large number of nodes, this PR does this call in asynchronously to have total waiting time reduced.

Which issue(s) this PR fixes:

None

Does this PR introduce a user-facing change?

No

Additional documentation e.g., KEPs (Kubernetes Enhancement Proposals), usage docs, etc.:

None

[k8s-ci-robot]

Hi @abdelrahman882. Thanks for your PR.

I'm waiting for a kubernetes 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.

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[x13n]

Thanks!

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: abdelrahman882, x13n

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• cluster-autoscaler/OWNERS [x13n]

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