test/integration/auth: fix data race

[pohly]

What type of PR is this?

/kind bug
/kind failing-test

What this PR does / why we need it:

"username" gets read by one goroutine and written by another. Therefore it must be protected by a mutex to avoid triggering the race detector.

Which issue(s) this PR fixes:

WARNING: DATA RACE
Read at 0x00c0037d8ae0 by goroutine 10105:
  k8s.io/kubernetes/test/integration/auth.TestSelfSubjectAccessReview.func1()
      /home/prow/go/src/k8s.io/kubernetes/_output/local/go/src/k8s.io/kubernetes/test/integration/auth/accessreview_test.go:155 +0x84
  k8s.io/kubernetes/vendor/k8s.io/apiserver/pkg/authentication/authenticator.RequestFunc.AuthenticateRequest()
      /home/prow/go/src/k8s.io/kubernetes/_output/local/go/src/k8s.io/kubernetes/vendor/k8s.io/apiserver/pkg/authentication/authenticator/interfaces.go:51 +0x36
  k8s.io/kubernetes/vendor/k8s.io/apiserver/pkg/endpoints/filters.withAuthentication.func1()
      /home/prow/go/src/k8s.io/kubernetes/_output/local/go/src/k8s.io/kubernetes/vendor/k8s.io/apiserver/pkg/endpoints/filters/authentication.go:63 +0x338
  net/http.HandlerFunc.ServeHTTP()
      /home/prow/go/src/k8s.io/kubernetes/_output/local/.gimme/versions/go1.20.2.linux.amd64/src/net/http/server.go:2122 +0x4d
  k8s.io/kubernetes/vendor/k8s.io/apiserver/pkg/endpoints/filterlatency.trackStarted.func1()
      /home/prow/go/src/k8s.io/kubernetes/_output/local/go/src/k8s.io/kubernetes/vendor/k8s.io/apiserver/pkg/endpoints/filterlatency/filterlatency.go:94 +0x4b5
  net/http.HandlerFunc.ServeHTTP()
      /home/prow/go/src/k8s.io/kubernetes/_output/local/.gimme/versions/go1.20.2.linux.amd64/src/net/http/server.go:2122 +0x4d
  k8s.io/kubernetes/vendor/k8s.io/apiserver/pkg/server/filters.(*timeoutHandler).ServeHTTP.func1()
      /home/prow/go/src/k8s.io/kubernetes/_output/local/go/src/k8s.io/kubernetes/vendor/k8s.io/apiserver/pkg/server/filters/timeout.go:124 +0xdb

Previous write at 0x00c0037d8ae0 by goroutine 5209:
  k8s.io/kubernetes/test/integration/auth.TestSelfSubjectAccessReview()
      /home/prow/go/src/k8s.io/kubernetes/_output/local/go/src/k8s.io/kubernetes/test/integration/auth/accessreview_test.go:219 +0x804
  testing.tRunner()
      /home/prow/go/src/k8s.io/kubernetes/_output/local/.gimme/versions/go1.20.2.linux.amd64/src/testing/testing.go:1576 +0x216
  testing.(*T).Run.func1()
      /home/prow/go/src/k8s.io/kubernetes/_output/local/.gimme/versions/go1.20.2.linux.amd64/src/testing/testing.go:1629 +0x47

Does this PR introduce a user-facing change?

NONE

[k8s-ci-robot]

Please note that we're already in Test Freeze for the release-1.27 branch. This means every merged PR will be automatically fast-forwarded via the periodic ci-fast-forward job to the release branch of the upcoming v1.27.0 release.

Fast forwards are scheduled to happen every 6 hours, whereas the most recent run was: Wed Apr 5 10:36:42 UTC 2023.

[k8s-ci-robot]

This issue is currently awaiting triage.

If a SIG or subproject determines this is a relevant issue, they will accept it by applying the triage/accepted label and provide further guidance.

The triage/accepted label can be added by org members by writing /triage accepted in a comment.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[dims]

/retest

[dims]

/approve
/lgtm

[k8s-ci-robot]

LGTM label has been added.

Git tree hash: 463bce26cf4246d23c268cbb18a273a50d443bbd

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: dims, pohly

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• test/OWNERS [dims,pohly]

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