In containerd 2.0 source tree, this constant is under `internal`, so we can't import it directly. So instead re-declare it as a Talos constant. Doing this multi-staged, as `go-talos-support` is using it as well, and to update it to stop importing old containerd library I need first to declare the constant in Talos source tree. Signed-off-by: Andrey Smirnov <andrey.smirnov@siderolabs.com>