Fix for isotope abundance parsing (#2003)

* Really hacky fix for the 'raw' isotope abundance parsing, someone should fix this properly

* Second attempt at fixing this, pretty hacky again getting the model attributtes in the plasma but at least it runs

tardis/plasma/standard_plasmas.py

@@ -251,7 +251,10 @@ def assemble_plasma(config, model, atom_data=None):
 
     if not model.raw_isotope_abundance.empty:
         plasma_modules += isotope_properties
-        kwargs.update(isotope_abundance=model.raw_isotope_abundance)
+        isotope_abundance = model.raw_isotope_abundance.loc[
+            :, model.v_boundary_inner_index : model.v_boundary_outer_index - 1
+        ]
+        kwargs.update(isotope_abundance=isotope_abundance)
 
     kwargs["helium_treatment"] = config.plasma.helium_treatment