pgsql: doc: clarify description for log_startup_progress_interval

doc: clarify description for log_startup_progress_interval

Reported-by: Elena Indrupskaya

Discussion: /messages/by-id/0af43b49-1646-93d0-ccf1-bb3c635c8c6f@postgrespro.ru

Author: Elena Indrupskaya

Backpatch-through: 15

Branch
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REL_15_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/d2d67949f5ca95cf4bd66d849e947f3bbe065e0d

Modified Files
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doc/src/sgml/config.sgml | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)