Panic on unchecked cast: interface conversion: interface {} is cache.DeletedFinalStateUnknown, not *unstructured.Unstructured

[Daimanta]

Describe the bug
We have set up an argo eventsource in our kubernetes cluster. Regularly (but unpredictably), the eventsources crashes in a panic. The panic message is a consistent problem, namely that a cast of an interface is done without checking.

Here is an example of a panic stack trace:

goroutine 159 [running]:
github.com/argoproj/argo-events/eventsources/sources/resource.passFilters(0xffffffffffffffff?, 0xffffffffffffffff?, {0x1?, 0x0?, 0x5b89900?}, 0x1?)
	/home/runner/work/argo-events/argo-events/eventsources/sources/resource/start.go:290 +0xa53
github.com/argoproj/argo-events/eventsources/sources/resource.(*EventListener).StartListening.func2(0xc001a59b60)
	/home/runner/work/argo-events/argo-events/eventsources/sources/resource/start.go:131 +0x6b
github.com/argoproj/argo-events/eventsources/sources/resource.(*EventListener).StartListening.func3()
	/home/runner/work/argo-events/argo-events/eventsources/sources/resource/start.go:178 +0x122
created by github.com/argoproj/argo-events/eventsources/sources/resource.(*EventListener).StartListening in goroutine 93
	/home/runner/work/argo-events/argo-events/eventsources/sources/resource/start.go:173 +0x8e8

Checking the start.go:290 we can see an unchecked cast. An *unstructured.Unstructured is expected but in this case a cache.DeletedFinalStateUnknown is provided.

To Reproduce
Unfortunately, this is a thing that happens sometimes and we have a difficult time finding out when the specified panic happens.
In general, passing an *InformerEvent with an Obj that is not *unstructured.Unstructured, will fail the unchecked cast.

Expected behavior
If the InformerEvent Obj is not an *unstructured.Unstructured, it should be ignored in the passFilters function. In general, the eventsource should not crash for any reason, in this case when an unexpected type is encountered.

Environment (please complete the following information):

• Kubernetes: v1.29.4
• Argocli: v3.5.6
• Argo Events: v1.9.2

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