Support structured logging

[bells17]

What type of PR is this?

/kind feature

What this PR does / why we need it:

I've added JSON logging and changed to use structured logging (e.g., klog.InfoS) in this PR.
With this change, it is now possible to output the logs of the external-health-monitor container in JSON format.
Running the container with the --logging-format=json option will output the logs in JSON format.

In addition, I've modified the log messages based on the following guideline:
https://github.com/kubernetes/community/blob/master/contributors/devel/sig-instrumentation/migration-to-structured-logging.md#remove-string-formatting-from-log-message

I’ve update the klog functions in use according to the guidelines provided below, and I've confirmed that they pass the logcheck tests:
https://github.com/kubernetes/community/blob/master/contributors/devel/sig-instrumentation/migration-to-structured-logging.md#change-log-functions

$ logcheck cmd/csi-external-health-monitor-controller/main.go
$ logcheck ./pkg/controller/
$ logcheck ./pkg/csi-handler/
$ logcheck ./pkg/csi-handler/
$ logcheck ./pkg/mock/
$ logcheck ./pkg/util/

related PR: kubernetes-csi/livenessprobe#202

Which issue(s) this PR fixes:

Special notes for your reviewer:

# The logs below were outputted because the program was running on MacOS.
$ go run cmd/csi-external-health-monitor-controller/main.go --logging-format=json
{"ts":1692983306225.366,"caller":"csi-external-health-monitor-controller/main.go:103","msg":"Version","v":0,"version":"unknown"}
{"ts":1692983306225.402,"caller":"csi-external-health-monitor-controller/main.go:117","msg":"Failed to build a Kubernetes config","err":"unable to load in-cluster configuration, KUBERNETES_SERVICE_HOST and KUBERNETES_SERVICE_PORT must be defined"}
exit status 1

$ go run cmd/csi-external-health-monitor-controller/main.go
I0826 02:08:31.658543   19448 main.go:103] "Version" version="unknown"
E0826 02:08:31.658664   19448 main.go:117] "Failed to build a Kubernetes config" err="unable to load in-cluster configuration, KUBERNETES_SERVICE_HOST and KUBERNETES_SERVICE_PORT must be defined"
exit status 1

Does this PR introduce a user-facing change?:

Added support structured logging

[k8s-ci-robot]

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[k8s-ci-robot]

Hi @bells17. Thanks for your PR.

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[xing-yang]

/ok-to-test

[xing-yang]

Hi @bells17, it looks like you are not a member yet. Please feel free to open an issue here and apply for membership in kubernetes-csi org.

[bells17]

I apologize for the oversight. I've noticed that the klog functions in use are not aligned with the guidelines below, so I will be changing the status of the Pull Request to Draft for now:
https://github.com/kubernetes/community/blob/master/contributors/devel/sig-instrumentation/migration-to-structured-logging.md#change-log-functions

[bells17]

The changes are done, so I've changed the PR status back to ready.

[xing-yang]

Can you keep this at InfoS?

[bells17]

@xing-yang Sorry for the mistake. I've updated it to use InfoS.

[xing-yang]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: bells17, xing-yang

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