Thread: pgsql: Add posting list tuple amcheck test case.

Add posting list tuple amcheck test case.

Add a test case to contrib/amcheck that creates coverage of code paths
that are used to verify posting list tuples (tuples created when
deduplication merges together existing tuples to avoid a leaf page
split).

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/20c6905dee43a8888090674cb3db9f953ae7f646

Modified Files
--------------
contrib/amcheck/expected/check_btree.out | 11 ++++++++++-
contrib/amcheck/sql/check_btree.sql      |  7 ++++++-
2 files changed, 16 insertions(+), 2 deletions(-)