The SQS seeder and the Poller seeder are removed, they weren't
adapted to the linear synchronization process and they are not
required anymore.
Also, all related classes and dependencies that where used by
these tasks were removed too.
The task runs frequently polling the xsn service for its latest block,
then, it calls the LedgerSynchronizerService to ensure that block
gets into the ledger database.
This is a replacement for the SQSSeederModule, instead
of requiring AWS SQS to sync the database, we poll the
latest block from the rpc server every minute.
As reuse most of the logic from the SQS seeding approach,
this could be a good replacement to remove the AWS
dependency, at the moment, the idea is to use this new
module locally.
Alexis Hernandez