Reset metric observed by TestProxyHandler for repeatable test runs.

[benluddy]

This test expects x509_missing_san_total to be 1. When run with
-test.count greater than 1, that expectation is unmet for all but the
first test run.

What type of PR is this?

/kind bug
/kind failing-test

What this PR does / why we need it:

Fixes TestProxyHandler, which depends on the value of a global counter, when tests are executed with -test.count greater than 1.

Which issue(s) this PR fixes:

Fixes #107059

Special notes for your reviewer:

Does this PR introduce a user-facing change?

NONE

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

[k8s-ci-robot]

Hi @benluddy. 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 /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.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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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.

[aojea]

/ok-to-test
/lgtm

[aojea]

go test -v k8s.io/kube-aggregator/pkg/apiserver -run TestProxyHandler -count 2
=== RUN   TestProxyHandler
E1215 23:28:54.849364   67930 handler_proxy.go:148] error resolving test-ns/bad-service: unresolveable
2021/12/15 23:28:54 http: TLS handshake error from 127.0.0.1:37388: remote error: tls: bad certificate
2021/12/15 23:28:54 http: TLS handshake error from 127.0.0.1:46674: remote error: tls: bad certificate
--- PASS: TestProxyHandler (0.02s)
=== RUN   TestProxyHandler
E1215 23:28:54.874326   67930 handler_proxy.go:148] error resolving test-ns/bad-service: unresolveable
2021/12/15 23:28:54 http: TLS handshake error from 127.0.0.1:49672: remote error: tls: bad certificate
2021/12/15 23:28:54 http: TLS handshake error from 127.0.0.1:46572: remote error: tls: bad certificate
    handler_proxy_test.go:380: expected the x509_missing_san_total to be 1, but it's 2
--- FAIL: TestProxyHandler (0.01s)
FAIL
FAIL	k8s.io/kube-aggregator/pkg/apiserver	0.059s
FAIL

with this PR

$ go test -v k8s.io/kube-aggregator/pkg/apiserver -run TestProxyHandler -count 2
=== RUN   TestProxyHandler
E1215 23:29:26.432457   73064 handler_proxy.go:148] error resolving test-ns/bad-service: unresolveable
2021/12/15 23:29:26 http: TLS handshake error from 127.0.0.1:50898: remote error: tls: bad certificate
2021/12/15 23:29:26 http: TLS handshake error from 127.0.0.1:52016: remote error: tls: bad certificate
--- PASS: TestProxyHandler (0.03s)
=== RUN   TestProxyHandler
2021/12/15 23:29:26 http: TLS handshake error from 127.0.0.1:40362: remote error: tls: bad certificate
2021/12/15 23:29:26 http: TLS handshake error from 127.0.0.1:52050: remote error: tls: bad certificate
E1215 23:29:26.482886   73064 handler_proxy.go:148] error resolving test-ns/bad-service: unresolveable
--- PASS: TestProxyHandler (0.02s)
PASS
ok  	k8s.io/kube-aggregator/pkg/apiserver	0.078s

[benluddy]

/retest

[fedebongio]

/triage accepted

[aojea]

@liggitt for approval

[liggitt]

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: benluddy, liggitt

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• staging/src/k8s.io/kube-aggregator/OWNERS [liggitt]

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