fix: use dl.k8s.io, not kubernetes-release bucket

[brcorey]

What type of PR is this?

/kind cleanup /kind deprecation

What this PR does / why we need it:

There are still references to https://storage.googleapis.com/kubernetes-release instead of https://dl.k8s.io/

dl.k8s.io is the correct advertised download host and will eventually move to be fastly shielding a fully community-owned bucket

ref: https://github.com/kubernetes/k8s.io/issues/2396

[k8s-ci-robot]

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[k8s-ci-robot]

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[rjsadow]

/ok-to-test

[rjsadow]

/lgtm Thanks!

[rjsadow]

@dgrisonnet can you please take a peek at this?

/assign @dgrisonnet /priority important-soon

[dgrisonnet]

Thanks @brcorey!

/lgtm /approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: brcorey, dgrisonnet

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