fix: panic in util.GVRFromType for structured types

[L3n41c]

What this PR does / why we need it:

Make util.GVRFromType able to process structured types and not only unstructured ones.

How does this change affect the cardinality of KSM: (increases, decreases or does not change cardinality)

Does not change.

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 [Bug] Inconsistency between customresource interface and customresource causes panic #2202

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[mrueg]

Thanks, makes sense to me.

/lgtm

/hold
for others to review.

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: L3n41c, mrueg

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