Remove index drop script

Author: viacheslavkol

src/main/resources/changelog/changelog-master.xml

@@ -23,5 +23,4 @@
   <include file="changes/v6.0/add_target_tenant_id_to_reindex_status.xml" relativeToChangelogFile="true"/>
   <include file="changes/v6.0/add_staging_time_columns_to_reindex_status.xml" relativeToChangelogFile="true"/>
   <include file="changes/v6.0/create_consortium_member_reindex_status_function.xml" relativeToChangelogFile="true"/>
-  <include file="changes/v6.0/drop_duplicate_instance_classification_index.xml" relativeToChangelogFile="true"/>
 </databaseChangeLog>