Ref: https://github.com/containerd/containerd/blob/release/2.0/docs/cri/config.md

Since this is a breaking change, add support for a new v3 template file. If no v3 template is present, fall back to checking for the legacy v2 template and render the old structure.
Signed-off-by: Brad Davidson <brad.davidson@rancher.com>
(cherry picked from commit bc459723)
Signed-off-by: Brad Davidson <brad.davidson@rancher.com>