Update Readme to reflect new way of obtaining deb/rpm packages

[dionysius]

What happened:

Followup for #1244. It is time to reflect the correct repo/link in the Readme in some way.

What you expected to happen:

The Readme doesn't send me to outdated and unmaintained repositories.

Anything else we need to know?:

Quickly checked that cri-tools as a package indeed exists there

[saschagrunert]

Thank you for the suggestion @dionysius! Do you think that you'd like to contribute that change?

[dionysius]

There doesn't exist a good place to link to reliably longterm

• https://kubernetes.io/blog/2023/08/15/pkgs-k8s-io-introduction/ is a "blog post"
• https://kubernetes.io/docs/tasks/tools/install-kubectl-linux/#install-using-native-package-management is only for kubectl
• https://kubernetes.io/docs/reference/tools/ doesn't offer/explain installation

Needs to be escalated to documentation