fix: update k3s, disable weave for all packages

General MR

Updates k3s to 1.28 (rancher/k3s:v1.27.4-k3s1 -> rancher/k3s:v1.28.6-k3s2), disables weave by default.

Summary

After some research and testing, I was able to get flannel working with all-package pipelines. This MR disables weave for all-packages pipelines and for all pipelines running k3d. K3d will now use the default CNI, flannel. The updated k3s image includes a newer build of kube-router, which was previously causing deployment bottlenecks because of buggy code with the NetworkPolicies controller.

Relevant logs/screenshots

n/a

Linked Issue

relates https://repo1.dso.mil/groups/big-bang/-/epics/278

relates https://repo1.dso.mil/big-bang/bigbang/-/issues/1972