duplicate logging in pg_createsubscriber

Hi hackers,

While reviewing pg_createsubscriber logs (in another thread) I saw
some unexpected (almost) duplicate consecutive logs for the slot
creation in --dry-run mode.

e.g.
----------
pg_createsubscriber: creating the replication slot
"pg_createsubscriber_16386_e9a70df3" in database "db2"
pg_createsubscriber: create replication slot
"pg_createsubscriber_16386_e9a70df3" on publisher
----------

It didn't look right to me.

I found the code is doing:
- pg_log_info("creating the replication slot unconditional inside
create_logical_replication_slot
- pg_log_info("create replication slot...") immediately after call to
create_logical_replication_slot

Perhaps that 2nd log was once supposed to say "created" (past tense),
but even that seemed redundant.

Here is a small patch to remove the log duplication by keeping only
the log *within* the function.

Thoughts?

======
Kind Regards,
Peter Smith.
Fujitsu Asutralia