Adding checkIndexRefs to 22.0-mc20
This MR adds the checkIndexRefs.py test as done in master by !50163 (merged). This is needed for the updated version of the derivation TCTs !50385 (merged).
This MR adds the checkIndexRefs.py test as done in master by !50163 (merged). This is needed for the updated version of the derivation TCTs !50385 (merged).