pgsql: Fix constant when extracting timestamp from UUIDv7.

Fix constant when extracting timestamp from UUIDv7.

When extracting a timestamp from a UUIDv7, a conversion from
milliseconds to microseconds was using the incorrect constant
NS_PER_US instead of US_PER_MS. Although both constants have the same
value, this fix improves code clarity by using the semantically
correct constant.

Backpatch to v18, where UUIDv7 was introduced.

Author: Erik Nordström <erik(at)tigerdata(dot)com>
Reviewed-by: Andrey Borodin <x4mmm(at)yandex-team(dot)ru>
Discussion: https://postgr.es/m/CACAa4V+i07eaP6h4MHNydZeX47kkLPwAg0sqe67R=M5tLdxNuQ@mail.gmail.com
Backpatch-through: 18

Branch
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REL_18_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/83773eaf657898a0c747deac7da37516124347c1

Modified Files
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src/backend/utils/adt/uuid.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)