pgsql: Give partitioned table "p" in regression tests a less generic na

Give partitioned table "p" in regression tests a less generic name.

And don't drop it, so that we improve the coverage of the pg_upgrade
regression tests.

Amit Langote, per a gripe from Tom Lane

Discussion: http://postgr.es/m/9071.1488863082@sss.pgh.pa.us

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/aa56671836e6f80dc3bdc917dfc860ac10b822be

Modified Files
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src/test/regress/expected/alter_table.out | 1 +
src/test/regress/expected/insert.out | 104 ++++++++++++++---------------
src/test/regress/expected/sanity_check.out | 9 ++-
src/test/regress/sql/alter_table.sql | 1 +
src/test/regress/sql/insert.sql | 69 +++++++++----------
src/test/regress/sql/sanity_check.sql | 2 +-
6 files changed, 95 insertions(+), 91 deletions(-)