Fix panic in NodeDeletionBatcher.AddNode

[com6056]

What type of PR is this?

/kind bug

What this PR does / why we need it:

Fixes a panic in NodeDeletionBatcher.AddNode. When deleteNodesFromCloudProvider has an error, sometimes nodeGroup will be nil so we should pass along the nodeGroupId we already have from scheduleDeletion instead.

Which issue(s) this PR fixes:

Fixes #5891

Special notes for your reviewer:

Does this PR introduce a user-facing change?

NONE

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: com6056
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[k8s-ci-robot]

PR needs rebase.

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[x13n]

Thanks for the change, but I think it already got fixed as a side effect of #5695

/close

[k8s-ci-robot]

@x13n: Closed this PR.

In response to this:

Thanks for the change, but I think it already got fixed as a side effect of #5695

/close

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