Improper GVR formatting causing failed informer deregistration

[Gonfidel]

Description

Observed Behavior:
When testing RGD creation and deletion using the following sample: example/kubernetes/webapp/rg.yaml, informers are successfully registered but fail to be cleaned up due to pkg\metadata\groupversion.go#GetResourceGraphDefinitionInstanceGVR returning an improperly formatted GVR. This finding also blocks #198 due to relying on the same gvr reference to deregister queues or gvrSets.

Proposed GVR:

schema.GroupVersionResource{
-		Group:    fmt.Sprintf("%s.%s", pluralKind, group),
+		Group:    group,
		Version:  apiVersion,
		Resource: pluralKind,
	}

Expected Behavior:
Successfully deregister informers on DynamicController#StopServiceGVK

Reproduction Steps (Please include ResourceGraphDefinition and Instances files):
Apply examples\kubernetes\webapp\rg.yaml and delete it with a debugger in DynamicController#StopServiceGVK. We perform an early return after not finding the informer due to the name mismatch

Versions:

• kro version: 0.2.1
• Kubernetes Version (kubectl version): v1.30.2

Involved Controllers:

• Controller URLs and Versions (if applicable): KRO RGD Controller passing GVR to Dynamic Controller

Error Logs (if applicable)**:
No logs, just early termination and no errors or warnings

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Which option describes the most your issue?

ResourceGraphDefinition (Create, Update, Deletion)