[2.26] Make Kubernetes v1.30.6 default

[robertvolkmann]

What type of PR is this?

/kind feature

What this PR does / why we need it:

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

Make Kubernetes v1.30.6 default 
Add hashes for Kubernetes 1.30.5, 1.29.8-10, and 1.28.13-15

[k8s-ci-robot]

Hi @robertvolkmann. 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.

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[mzaian]

/ok-to-test

[VannTen]

/lgtm /approve

Thanks

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: robertvolkmann, VannTen

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Needs approval from an approver in each of these files: - ~~[OWNERS](https://github.com/kubernetes-sigs/kubespray/blob/release-2.26/OWNERS)~~ [VannTen] Approvers can indicate their approval by writing `/approve` in a comment Approvers can cancel approval by writing `/approve cancel` in a comment