bump containerd binary for 1.11.0-rc4

this bumps the containerd binary in the Dockerfiles
for 1.11.0-rc4, to include https://github.com/docker/containerd/pull/184

NOTE: the hack/vendor.sh commit is NOT updated in this
      patch; there's no reason to update containerd there

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>