pgsql: doc PG 17 relnotes: improve text for pg_walfile_name*()

doc PG 17 relnotes: improve text for pg_walfile_name*()

Reported-by: Yugo Nagata

Discussion: /messages/by-id/20240726132224.3a77e79c4e563125c451e865@sraoss.co.jp

Backpatch-through: 17 only

Branch
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REL_17_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/6b84ae65fb9af2152ac26675635459069647d555

Modified Files
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doc/src/sgml/release-17.sgml | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)