pgsql: doc: clarify that "excluded" ON CONFLICT is a single row

doc: clarify that "excluded" ON CONFLICT is a single row

Original patch by David G. Johnston.

Reported-by: David G. Johnston

Discussion: /messages/by-id/CAKFQuwa4J0+WuO7kW1PLbjoEvzPN+Q_j+P2bXxNnCLaszY7ZdQ@mail.gmail.com

Backpatch-through: 10

Branch
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REL_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/5790aa46af8e6f8c6b090a931fc18b42002e4f54

Modified Files
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doc/src/sgml/ref/insert.sgml | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)