Thread: pgsql: Fix mark-and-restore-skipping test case to not be a self-join.

Fix mark-and-restore-skipping test case to not be a self-join.

There isn't any good reason for this test to be a self-join rather
than a join between separate tables, except that it saved a couple
of SQL commands for setup.  A proposed patch to optimize away
self-joins breaks the test, so adjust it to avoid that happening.

Discussion: https://postgr.es/m/64486b0b-0404-e39e-322d-0801154901f3@postgrespro.ru

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/24d08f3c0a1f04ea8bac68eb3aa3b069680e43f5

Modified Files
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src/test/regress/expected/join.out | 20 ++++++++++++--------
src/test/regress/sql/join.sql      | 15 ++++++++++-----
2 files changed, 22 insertions(+), 13 deletions(-)