Add input option "ones" for solids monitors

docs/source_docs/user_guide/inputs/species_defs.rst

@@ -188,9 +188,6 @@ outflow boundary condition pressure which is set here to 1 atmosphere.
    species.diffusivity = constant
    species.diffusivity.constant  = 1.9e-5
 
-   species.O2.molecular_weight = 31.99880e-3
-   species.N2.molecular_weight = 28.01340e-3
-
    species.specific_heat = NASA7-poly
 
    # Oxygen