pgsql: Doc: fix bogus example about ambiguous timestamps.

Doc: fix bogus example about ambiguous timestamps.

I had a brain fade in commit d32899157, and used 2:30AM as the
example timestamp for both spring-forward and fall-back cases.
But it's not actually ambiguous at all in the fall-back case,
because that transition is from 2AM to 1AM under USA rules.
Fix the example to use 1:30AM, which *is* ambiguous.

Noted while answering a question from Aleksander Alekseev.
Back-patch to all supported branches.

Discussion: https://postgr.es/m/2191355.1641828552@sss.pgh.pa.us

Branch
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REL_13_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/2180833ba90e9657a7e622b419194763890c8a6d

Modified Files
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doc/src/sgml/datetime.sgml | 20 +++++++++-----------
1 file changed, 9 insertions(+), 11 deletions(-)