pgsql: doc: remove useless MERGE example

doc: remove useless MERGE example

Reported-by: dwayne.towell@gmail.com

Discussion: /messages/by-id/167699245721.1902146.6479762301617101634@wrigleys.postgresql.org

Backpatch-through: master

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/4a9effe45ee96f7105ba19285eff18a634bfee01

Modified Files
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doc/src/sgml/ref/merge.sgml | 17 -----------------
1 file changed, 17 deletions(-)