refactor(swap_encryption/pr3): thin benchmark using BaseResource pattern

- Prepare() uses SwapNodePool + SwapDaemonSet from spec.resources
- Cleanup() is empty - PKB framework auto-deletes spec.resources
- All _pod_exec(pod, ...) calls replaced with daemonset.PodExec(...)
- Add _configure_eks_kubelet_swap() stub (deferred to PR #6780)
- Fix COS_CONTAINERD -> UBUNTU_CONTAINERD (r3472549985)
- 7-job fio suite retained
- pyink --line-length=80 pass

Author: DevVegeta