remove strings.compare(), use string native operation

[knightXun]

I notice we use strings.Compare() in some code, we can remove it and use native operation.

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[k8s-reviewable]

This change is 

[k8s-ci-robot]

Hi @knightXun. Thanks for your PR.

I'm waiting for a kubernetes member to verify that this patch is reasonable to test. If it is, they should reply with @k8s-bot ok to test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[knightXun]

@ solty i made wrong operation....

[cblecker]

@k8s-bot ok to test

[ericchiang]

A note that strings.Compare's godoc recommends not using it.

Compare is included only for symmetry with package bytes. It is usually clearer and always faster to use the built-in string comparison operators ==, <, >, and so on.

/approve

[cblecker]

/assign

[cblecker]

/release-note-none
/lgtm

[smarterclayton]

/approve

[k8s-github-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: cblecker, ericchiang, knightXun, smarterclayton

Needs approval from an approver in each of these OWNERS Files:

• pkg/apis/OWNERS [smarterclayton]
• pkg/cloudprovider/OWNERS [smarterclayton]
• pkg/printers/OWNERS [smarterclayton]
• staging/src/k8s.io/kube-aggregator/OWNERS [smarterclayton]

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[k8s-github-robot]

Automatic merge from submit-queue (batch tested with PRs 44594, 44651)