Simplify the unregistration of csiplugin

[tedyu]

What type of PR is this?
/kind cleanup

What this PR does / why we need it:
This PR simplifies the unregistration of csiplugin by dropping SocketPluginHandlers.

Which issue(s) this PR fixes:
Addresses concerns raised in #88006 (comment)
Fixes #87282

NONE

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

[tedyu]

/assign @saad-ali

[tedyu]

/priority backlog

[saad-ali]

Thanks @tedyu
/lgtm
/approve

/test pull-kubernetes-conformance-kind-ga-only-parallel
/test pull-kubernetes-e2e-kind-ipv6

/hold
To let @taragu review

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: saad-ali, tedyu

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• pkg/kubelet/pluginmanager/OWNERS [saad-ali]

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[tedyu]

/retest

[taragu]

Looks good overall! Just one suggestion for consistency. The PluginInfo objects in actual_state_of_world_test.go need to be updated with the new fields to be added.

[tedyu]

@taragu
In operationGenerator#GenerateRegisterPluginFunc, handler is retrieved from pluginHandlers.
I looked at the test code where there is no pluginHandlers.

Can you be a bit specific on how the PluginInfo object should be populated in the test ?

[taragu]

@tedyu sure, here for example: https://github.com/kubernetes/kubernetes/blob/b54e7d92652797d8485596440960490d66c505be/pkg/kubelet/pluginmanager/cache/actual_state_of_world_test.go#L30 we can change it to the following just for completion purposes

pluginInfo := PluginInfo{
		SocketPath: "/var/lib/kubelet/device-plugins/test-plugin.sock",
		Timestamp:  time.Now(),
		Handler: nil,
		Name: "test",
	}

[tedyu]

@taragu
Your comment has been addressed.

[taragu]

/lgtm
Any idea why the tests aren't running?

[tedyu]

/hold cancel