Adjust handling units of measurement to changes in core.proto

[tnoczyns-volue]

Adjust to proto changes that will be done in https://github.com/Volue/energy-mesh/issues/4662.

The changes won't break the Python SDK API:

• The unit_of_measurement in SimpleAttributeDefinition, TimeseriesAttributeDefinition and TimeseriesResource should be left as string type.
• The new_unit_of_measurement parameter in update_timeseries_resource_info should be left as a string, but in the implementation of update_timeseries_resource_info we should use ListUnitsOfMeasurement RPC¹ to map the unit of measurement name to ID and use the ID in the updated UpdateTimeseriesResource RPC.

With this approach the:

• Python SDK API is compatible with older versions.
• Users can still work with units of measurements expressed as strings, which could be handier.
• We still have the option to extend the new_unit_of_measurement in update_timeseries_resource_info to accept also IDs and express unit_of_measurement in SimpleAttributeDefinition, TimeseriesAttributeDefinition and TimeseriesResource by new class UnitOfMeasurement instead of string.

Footnotes

1. This RPC will be added in https://github.com/Volue/energy-mesh/issues/4701. ↩