PSPNG references PIT tables, not changelog for group attributes during delete group events.

groupSearchAttributes defaults to "cn,gidNumber,samAccountName,objectclass", so it seems to be a reasonable assumption that a singleGroupSearch that utilizes group attributes mapped to those values(e.g. 'cn=${group.name}', gidNumber=${group.idIndex}, etc) should return a group. 

In cases where a provisioner uses an attribute that is not ${group.name} or ${group.extension} as a single group search parameter, issues arise during Group deletions.

When a provsioned group is deleted, the provisioner logs an error:

2019-03-11 10:29:00,074: [DefaultQuartzScheduler_Worker-6] ERROR Provisioner.evaluateJexlExpression(665) - - Jexl Expression SingleGroupSearchFilter '(&(objectclass=group)(gidNumber=${group.idIndex}))' could not be evaluated for subject 'null/null' and group 'uncg:apps:AAA_test:BravoGroupID(PIT)/null' which used variableMap '{extension=BravoGroupID, pitGroup=edu.internet2.middleware.grouper.pit.PITGroup@8ab224e1, displayName=uncg:apps:AAA_test:BravoGroupID, provisionerName=pspng_personBushyLdap, groupSearchBaseDn=ou=groups,dc=devauth,dc=uncg,dc=edu, groupAttributes={}, displayExtension=BravoGroupID, userSearchBaseDn=ou=accounts,dc=devauth,dc=uncg,dc=edu, provisionerType=LdapGroupProvisioner, groupCreationBaseDn=ou=groups,dc=devauth,dc=uncg,dc=edu, utils=edu.internet2.middleware.grouper.pspng.PspJexlUtils@4898a89b, stemAttributes={}, name=uncg:apps:AAA_test:BravoGroupID}'
edu.internet2.middleware.grouper.exception.ExpressionLanguageMissingVariableException: variable 'group.idIndex' is not defined in script: 'group.idIndex'

The provisioner is looking in the PIT tables for group.idIndex. It will always comes back as NULL since the group has already been deleted. 

This creates a constraint that only search filters using the group name can be used to delete groups during incremental changelog events.