chore: fix nodeClassRef conversion

[jigisha620]

Fixes #N/A

Description
When converting nodeClassRef from v1beta1 to v1, group would be empty if apiVersion is of the type karpenter.k8s.aws i.e. it does not contain the version. This PR adds the fix for it.

How was this change tested?
Tested on local cluster

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[k8s-ci-robot]

Hi @jigisha620. Thanks for your PR.

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[engedaam]

/lgtm

[coveralls]

Pull Request Test Coverage Report for Build 10293452407

Details

• 2 of 2 (100.0%) changed or added relevant lines in 2 files are covered.
• 9 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-0.08%) to 77.817%

---

Files with Coverage Reduction	New Missed Lines	%
pkg/controllers/node/termination/controller.go	2	66.47%
pkg/controllers/provisioning/scheduling/preferences.go	7	86.67%

Totals
Change from base Build 10292315970:	-0.08%
Covered Lines:	8882
Relevant Lines:	11414

---

💛 - Coveralls

[njtran]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: jigisha620, njtran

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