pgsql: Remove %error-verbose directive from jsonpath parser

Remove %error-verbose directive from jsonpath parser

None of the other bison parsers contains this directive, and it gives
rise to some unfortunate and impenetrable messages, so just remove it.

Backpatch to release 12, where it was introduced.

Per gripe from Erik Rijkers

Discussion: https://postgr.es/m/ba069ce2-a98f-dc70-dc17-2ccf2a9bf7c7@xs4all.nl

Branch
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REL_13_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/03cefe81484d563a7165e8fa57a03a33d4c5c188

Modified Files
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src/backend/utils/adt/jsonpath_gram.y  |  1 -
src/test/regress/expected/jsonpath.out | 34 +++++++++++++++++-----------------
2 files changed, 17 insertions(+), 18 deletions(-)