Fix #196: Force _CIPCode property to S or R in Molecule.to_rdkit when RDKit cannot figure out the atom chirality.
Fix #196: Force _CIPCode property to S or R in Molecule.to_rdkit when RDKit cannot figure out the atom chirality.

open-forcefield-group/openforcefield,openforcefield/openff-toolkit,open-forcefield-group/openforcefield,openforcefield/openff-toolkit,open-forcefield-group/openforcefield