Missing wait_for_replay_catchup in 035_standby_logical_decoding.pl

hi hackers,

while working on the issue reported by Noah in [1], I realized that there is an
issue in 035_standby_logical_decoding.pl.

The issue is here:

"
$node_standby->reload;

$node_primary->psql('postgres', q[CREATE DATABASE testdb]);
$node_primary->safe_psql('testdb', qq[CREATE TABLE decoding_test(x integer, y text);]);

# create the logical slots
create_logical_slots($node_standby, 'promotion_');

# create the logical slots on the cascading standby too
create_logical_slots($node_cascading_standby, 'promotion_');
"

We are not waiting for the standby/cascading standby to catchup (so that the create
database get replicated) before creating the replication slots (in testdb).

While, It's still not 100% sure that it will fix Noah's issue, I think this has to be fixed.

Please find, attached a patch proposal to do so.

Regards,

[1]: https://www.postgresql.org/message-id/20230411053657.GA1177147%40rfd.leadboat.com
--
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.com