pgsql: Fix name collision between concurrent regression tests.

Fix name collision between concurrent regression tests.

Commit f5bcd398addcbeb785f0513cf28cba5d1ecd2c8a introduced a test using
a table named "circles" in inherit.sql. Unfortunately, the concurrently
executed constraints test was already using that table name, so the
parallel regression tests would sometimes fail. Rename table to dodge
the problem. Per buildfarm.

Branch
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REL9_2_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/d86fb72c5c7ebf71e238ac87daa0c1f8043a1717

Modified Files
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src/test/regress/expected/inherit.out | 32 ++++++++++++++++----------------
src/test/regress/sql/inherit.sql | 16 ++++++++--------
2 files changed, 24 insertions(+), 24 deletions(-)