Support containerd NRI enablement

[vholer]

What I'd like:

I would like to use NRI feature in containerd, which should allow more reliable behaviour with KubeArmor (change implemented as part of kubearmor/KubeArmor#1674).

It would be nice to have a configuration option, e.g. settings.container-runtime.enable-nri, which might add following snippet into /etc/containerd/config.toml:

[plugins."io.containerd.nri.v1.nri"]
    # Enable NRI support in containerd.
    disable = false
    # Allow connections from externally launched NRI plugins. (through the NRI unix socket)
    disable_connections = false
    # plugin_registration_timeout is the timeout for a plugin to register after connection.
    plugin_registration_timeout = "5s"
    # plugin_request_timeout is the timeout for a plugin to handle an event/request.
    plugin_request_timeout = "2s"
    # socket_path is the path of the NRI socket to create for plugins to connect to.
    socket_path = "/var/run/nri/nri.sock"

[koooosh]

Hey @vholer , thanks for the feature request! Can you please clarify what you mean by NRI allowing "more reliable behaviour with KubeArmor"?