pgsql: doc: Move DEFAULT parameter on COPY reference page

doc: Move DEFAULT parameter on COPY reference page

The DEFAULT parameter seems most similar to the NULL parameter, so
move it next to it, instead of having it at the end of the parameter
list because it was the last one added.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/be2ab58f6227ef8ea341c3d9b9f99d53d56529a9

Modified Files
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doc/src/sgml/ref/copy.sgml | 28 ++++++++++++++--------------
1 file changed, 14 insertions(+), 14 deletions(-)