Errors in new templates

[cprivitere]

There are some minor errors in the new templates.

• apt-get remove line including docker.io bombs out and doesn't run (since docker.io isn't in the default apt repositories)
• Forgot to switch from installing containerd to containerd.io which was the whole point of adding the docker repositories.
• sandbox image sed line should add quotes around the sandbox image, otherwise containerd errors out due to config.toml being invalid