fix_initialization_states on property models untested and erroneous

[adam-a-a]

I noticed that fix_initialization_states methods were previously added to our prop models. I then noticed that conc_mol_comp["H2O"] would be unfixed if define_state was False for a given stateblock (e.g., outlet). However, conc_mol_comp does not exist on most of these property models, so I wondered how this was able to go through without errors arising, and it seems there are no tests for this method, and I don't see the method used anywhere, which is probably how this escaped detection.