pgsql: Remove unreferenced pg_opfamily entry.

Remove unreferenced pg_opfamily entry.

The entry with OID 4035, for GIST jsonb_ops, is unused; apparently
it was added in preparation for index support that never materialized.
Remove it, and add a regression test case to detect future mistakes
of the same kind.

Discussion: https://postgr.es/m/17188.1541379745@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/55f3d1029676ad53621716fd15faed5848c9f4cd

Modified Files
--------------
src/include/catalog/catversion.h         |  2 +-
src/include/catalog/pg_opfamily.dat      |  2 --
src/test/regress/expected/opr_sanity.out | 10 ++++++++++
src/test/regress/sql/opr_sanity.sql      |  8 ++++++++
4 files changed, 19 insertions(+), 3 deletions(-)