pgsql: Adjust largeobject regression test to leave a couple of LOs behi

Adjust largeobject regression test to leave a couple of LOs behind.

Since we commonly test pg_dump/pg_restore by seeing whether they can dump
and restore the regression test database, it behooves us to include some
large objects in that test scenario.

I tried to include a comment on one of these large objects to improve
the test scenario further ... but it turns out that pg_upgrade fails to
preserve comments on large objects, and its regression test notices
the discrepancy.  So uncommenting that COMMENT is a TODO for later.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/70ad7ed4e88d9de3273f2f875cfaa044a35dfa97

Modified Files
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src/test/regress/input/largeobject.source    |   26 ++++++++++++++++++++++++--
src/test/regress/output/largeobject.source   |   22 +++++++++++++++++++++-
src/test/regress/output/largeobject_1.source |   22 +++++++++++++++++++++-
3 files changed, 66 insertions(+), 4 deletions(-)