pgsql: Tweak new regression test case for better portability.

Tweak new regression test case for better portability.

Buildfarm says we get different plans on 32-bit and 64-bit platforms,
probably because of MAXALIGN-related differences in memory-consumption
calculations.  Add some dummy WHERE clauses so that the planner estimates
different sizes for the three generate_series() relations; that should
stabilize the choice of join order.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/d4d48a5edd9eb28a7f2ee2e4cbe20d984274982e

Modified Files
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src/test/regress/expected/pg_lsn.out |    8 ++++++--
src/test/regress/sql/pg_lsn.sql      |    2 ++
2 files changed, 8 insertions(+), 2 deletions(-)