Leverage error status in module state

[a-thaler]

Description
The state of a module was incorporated in the overall "Kyma" CR state in the past. An error state for "Kyma" indicated an operational problem. That got decoupled and and a bad module status will not trigger any operartional actions anymore. Instead it will be fully user facing and indicates a problem on user side.

Consequently, the state of the telemetry module should be calculated properly now, indicating:

• an error: for permanent problems
• a warning: for temporary or forecasted problems (aboutToExpire)

Criterias

• The module state leverages error as value appropriate
• Documentation got adjusted were needed