Bugfix/Cleanup/Stability of Raritan Residual current check

[nightwatcher74]

The Raritan PDU sends per default only a Crit value of 0,030A and no warn. This will be set to None and the check will crash. Becuase this is security sensitive, a WARN value will be set to CRIT and a CRIT value will be set also on WARN. So in all cases a CRIT Message will be set! I decided to make this solution because it is important to get an event in all cases because it can save lives.

I also merge the complete dataclasses to pydantic and add a funktion to easier get the capabilities of the Raritan device instead of check the bits itself. Funktions that are required as shared funktions when the legacy check will be rewirtten are moves to lib. The shared funktions can be included wir init.py: from cmk.plugins.raritan import (
InletSensorEnabledThresholds,
InletDeviceCapabilities,
InletPoleCapabilities,
RaritanData,
SensorValues,
Sensor,
PDU,
TYPE_MAPPING,
UNIT_MAPPING,
)

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