fix(eventhandler): trigger Node/Delete event

[sanposhiho]

What type of PR is this?

/kind bug

What this PR does / why we need it:

We didn't trigger Node/Delete event at all...

Which issue(s) this PR fixes:

Initially found at #110175 (comment), but we forgot to fix.

Special notes for your reviewer:

Does this PR introduce a user-facing change?

Fixed a bug which the scheduler didn't correctly tell plugins Node deletion.
This bug could impact all scheduler plugins subscribing to Node/Delete event, making the queue keep the Pods rejected by those plugins incorrectly at Node deletion. Among the in-tree plugins, PodTopologySpread is the only victim.

Additional documentation e.g., KEPs (Kubernetes Enhancement Proposals), usage docs, etc.:

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[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: sanposhiho

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[sanposhiho]

/hold
to go thru the approver's review.

/cc @alculquicondor @macsko

[sanposhiho]

@alculquicondor also, do we want to cherry-pick this?

[macsko]

/lgtm

[k8s-ci-robot]

LGTM label has been added.

Git tree hash: 46834776b54969e504483c58f7867b2ecf7cb157

[alculquicondor]

Right, the event doesn't seem to be used anywhere.

In any case, we should add a test, preferably integration.

[AxeZhan]

I added an integration test in #127387

kubernetes/test/integration/scheduler/plugins/plugins_test.go

Line 2889 in 8b484be

func TestUnscheduledPodEvents(t *testing.T) {

These two pr are a little similar, #127387 trigger unscheduledPod add/update//delete event, while this one triggers node/delete event.

Maybe the integration test in #127387 can be more general and we can reuse it here.