pgsql: Fix overly generic name in with.sql test.

Fix overly generic name in with.sql test.

Avoid the name "test". In the 10 branch, this could clash with
alter_table.sql, as seen in the build farm. That other instance was
already renamed in later branches by commit 2cf8c7aa, but it's good to
future-proof the name here too.

Back-patch to 10.

Reviewed-by: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Discussion: https://postgr.es/m/CA%2BhUKGJf4RAXUyAYVUcQawcptX%3DnhEco3SYpuPK5cCbA-F1eLA%40mail.gmail.com

Branch
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REL_11_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/81b12fb33a5eb499bc43ba4589e8c9a709d9eb5c

Modified Files
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src/test/regress/expected/with.out | 16 ++++++++--------
src/test/regress/sql/with.sql | 10 +++++-----
2 files changed, 13 insertions(+), 13 deletions(-)