_enthalpy_flow_term incorrectly used under _energy_density_term in generic modular property scaling

[aspitarl]

When running calculate_scaling_factors with a generic property and _energy_density_term it appears that the code has a typo that tries to incorrectly set the scaling factor of _enthalpy_flow_term

https://github.com/IDAES/idaes-pse/blob/5f3b33bf6ffdce40b085fab16820eb7d9812f67c/idaes/models/properties/modular_properties/base/generic_property.py#L2243-L2244

After changing this to self.energy_density_term I was able to calculate scaling factors correctly.