pgsql: Extend a test case a little

Extend a test case a little

This will possibly help a subsequent patch by making sure the notice
messages are distinct so that it's clear that they come out in the
right order.

Author: Fabien COELHO <coelho@cri.ensmp.fr>
Discussion: /messages/by-id/alpine.DEB.2.21.1904240654120.3407@lancre

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b3a9e9897ec702d56602b26a8cdc0950f23b29dc

Modified Files
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src/test/regress/expected/copydml.out | 16 ++++++++--------
src/test/regress/sql/copydml.sql | 4 ++--
2 files changed, 10 insertions(+), 10 deletions(-)