pg_createsubscriber: Remove failover replication slots on subscriber
After running pg_createsubscriber, these replication slots have no use
on subscriber, so drop them.
Author: Euler Taveira <euler.taveira@enterprisedb.com>
Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Discussion: https://www.postgresql.org/message-id/
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