[Release-1.30] - Bump containerd to v1.7.26

[brandond]

We're bumping to containerd v2.0.3 on other branches, on this branch we just need latest 1.7.

No bugs to fix, just a version bump.

• Fallback to default registry endpoint is broken when using "*" wildcard mirror in registries.yaml with containerd 2.0 #7827

[mdrahman-suse]

Validation on v1.30.11-rc1

$ rke2 -v
rke2 version v1.30.11-rc1+rke2r1 (674da4a8f9be57c61a7d5ff9bdcc3e1ebd58220a)
go version go1.23.6 X:boringcrypto

$ kubectl get nodes -o yaml | grep containerd -A1
      containerRuntimeVersion: containerd://1.7.26-k3s1
      kernelVersion: 6.8.0-1012-aws