🌱 envtest: fix nil pointer exception in Stop().

[guettli]

old code:

func (s *APIServer) Stop() error {
	if s.processState != nil {
		if s.processState.DirNeedsCleaning {
			s.CertDir = "" // reset the directory if it was randomly allocated, so that we can safely restart
		}
		if err := s.processState.Stop(); err != nil {
			return err
		}
	}
	return s.Authn.Stop()
}

If setup failed, and then Stop() gets called, s.Authn could be nil.

This PR checks if s.Auth is nil.

[k8s-ci-robot]

Hi @guettli. Thanks for your PR.

I'm waiting for a kubernetes-sigs 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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[sbueringer]

/ok-to-test

[sbueringer]

Thank you!

/lgtm
/approve

[k8s-ci-robot]

LGTM label has been added.

Git tree hash: a5fe2c94a93b09be4304d484c2204fd3eb5f8a7b

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: guettli, sbueringer

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