Prior to this commit, `/etc/containerd/config.toml` with no version was parsed as version 3. Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
Prior to this commit, `/etc/containerd/config.toml` with no version was parsed as version 3. Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>