[COMMITTERS] pgsql: Use less-generic table name in new regression test case.

Use less-generic table name in new regression test case.

Creating global objects named "foo" isn't an especially wise thing,
but especially not in a test script that has already used that name
for something else, and most especially not in a script that runs
in parallel with other scripts that use that name :-(

Per buildfarm.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/1c95f0b478a91b58391720dcda35bc032e582564

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