OPENDJ-2404: add back support for modify DN operations which just change case

Matthew Swift

25.45.2015 99b80cd414fd73af73dfa07be202fd32e9bc498d

 opendj-server-legacy/src/main/java/org/opends/server/backends/pluggable/EntryContainer.java

@@ -2023,7 +2023,10 @@
                                           getMatchedDN(txn, newSuperiorDN),
                                           null);
            }
            if (dn2id.get(txn, newTargetDN) != null)

            // Check that an entry with the new name does not already exist, but take care to handle the case where
            // the user is renaming the entry with an equivalent name, e.g. "cn=matt" to "cn=Matt".
            if (!oldTargetDN.equals(newTargetDN) && dn2id.get(txn, newTargetDN) != null)
            {
              throw new DirectoryException(ResultCode.ENTRY_ALREADY_EXISTS,
                                           ERR_MODIFYDN_ALREADY_EXISTS.get(newTargetDN));