Detect v2 schema and use correct long form of cri plugin

[dsyer]

CRI has a v2 schema that seems to be the default in a lot of containerd installations. It uses a "long" form for the plugin id in the TOML config file.

Fixes #881. I couldn't find any tests for this script, and I don't really have time to learn how to build the whole project, but I did test this change with my config.toml and it worked.

[grahamwhaley]

Thanks @dsyer . The PR requires a few tweaks to meet our contribution guidelines, or the CI will kick it out. I'll list the ones I can see here. But, if you really don't have time to re-spin, then shout, and we can pick this up and re-PR it (and credit you).

• commit subject line needs to have a submodule prefix, so 'kata-deploy: detect v2....'
• you need to sign the commits with git - 'git commit -s'
• your 'Fixes: #nnn' probably needs to be on its own line, and in the commit, not the PR message

[grahamwhaley]

/test thanks for the update @dsyer

[grahamwhaley]

/AzurePipelines run

[grahamwhaley]

/test-ubuntu

[azure-pipelines[bot]]

Azure Pipelines successfully started running 2 pipeline(s).

[devimc]

/test-snap