Replacing referenced issues for scale down issue

[clsacramento]

Since istio/istio#19395 is currently closed, it looks like the known issue is no longer relevant, while in fact is is still pending on kubernetes/autoscaler#3947.

This is just a trivial replacement of the reference issue. I hope it is ok.

[ ] Configuration Infrastructure
[x] Docs
[ ] Installation
[ ] Networking
[ ] Performance and Scalability
[ ] Policies and Telemetry
[ ] Security
[ ] Test and Release
[ ] User Experience
[ ] Developer Infrastructure

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[istio-testing]

Hi @clsacramento. Thanks for your PR.

I'm waiting for a istio 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.

I understand the commands that are listed here.

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.

[mandarjog]

Lgtm

[craigbox]

/ok-to-test

[ericvn]

/cherry-pick release-1.10

[istio-testing]

@ericvn: new pull request created: #9974

In response to this:

/cherry-pick release-1.10

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.