First, use Vaccum Full or Vaccumlo if storing largeobject for clearing bloat, If you are running a script, dump it outside the RDS, such as you can dump it to EC2, and then apply PG_repack on the schema and then restore it to RDS.
As you know such services are not available on RDS.
I am trying to schedule pg_repack from pg_cron in RDS postgres environment on avoid the bash on host EC2 to run run directly with in postgres instance.it getting successful but not clearing bloat by using repack fuction in pg_repack extension.please help on these to sort out .