fixup! fix array_cat_agg for pg upgrades

src/backend/distributed/sql/udfs/citus_finish_pg_upgrade/10.2-1.sql

@@ -24,6 +24,16 @@ BEGIN
     $cmd$;
     END IF;
 
+    /*
+     * Citus creates the array_cat_agg but because of a compatibility
+     * issue between pg13-pg14, we drop and create it during upgrade.
+     * And as Citus creates it, there needs to be a dependency to the
+     * Citus extension, so we create that dependency here.
+     * We are not using:
+     *  ALTER EXENSION citus DROP/CREATE AGGREGATE array_cat_agg
+     * because we don't have an easy way to check if the aggregate 
+     * exists with anyarray type or anycompatiblearray type.
+     */
     INSERT INTO pg_depend
     SELECT
         'pg_proc'::regclass::oid as classid,

src/backend/distributed/sql/udfs/citus_finish_pg_upgrade/latest.sql

@@ -24,6 +24,16 @@ BEGIN
     $cmd$;
     END IF;
 
+    /*
+     * Citus creates the array_cat_agg but because of a compatibility
+     * issue between pg13-pg14, we drop and create it during upgrade.
+     * And as Citus creates it, there needs to be a dependency to the
+     * Citus extension, so we create that dependency here.
+     * We are not using:
+     *  ALTER EXENSION citus DROP/CREATE AGGREGATE array_cat_agg
+     * because we don't have an easy way to check if the aggregate 
+     * exists with anyarray type or anycompatiblearray type.
+     */
     INSERT INTO pg_depend
     SELECT
         'pg_proc'::regclass::oid as classid,