pgsql: docs: Fix snapshot name in SET TRANSACTION docs.

docs: Fix snapshot name in SET TRANSACTION docs.

Commit 6c2003f8a1 changed the snapshot names mentioned in
SET TRANSACTION docs, however, there was one place that
the commit missed updating the name.

Back-patch to all supported versions.

Author: Japin Li
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/MEYP282MB1669BD4280044501165F8B07B64F9@MEYP282MB1669.AUSP282.PROD.OUTLOOK.COM

Branch
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REL_14_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/be032619d4b16e74025d04e027b587d6e11e7cbd

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