Allow to control the log chattiness of the Kubelet

[corvus-ch]

Context

By default, the log level of the Kubelet is set to debug. This generates a lot of noise in the logs. It also results in a huge amount of data stored within logging (Elastisearch). The log level should be configurable through the configuration hierarchy. Section "3. Persistent configuration for OCP 4.6 and later" in https://access.redhat.com/solutions/4619431 explains how this can be done.

[tobru]

This issue might belong into https://github.com/appuio/component-openshift4-nodes/issues?

[corvus-ch]

This issue might belong into https://github.com/appuio/component-openshift4-nodes/issues?

The issue asks for creating a MachineConfig. Doing so is not restricted to the openshift4-nodes component but can be done in any component. As a matter of facts, this component already does so (https://github.com/appuio/component-openshift4-logging/blob/b88b0c6/component/main.jsonnet#L51). So this issue is filed with the correct component.