pgsql: Unify some error messages - Mailing list pgsql-committers

Unify some error messages

We had essentially the same error in several different wordings.
Unify that.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/dca20013ebab0f0176e610a36b846d899af1d451

Modified Files
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src/backend/utils/adt/json.c                       |  4 ++--
src/backend/utils/adt/jsonb_util.c                 |  2 +-
.../ecpg/test/expected/sql-sqljson.stderr          |  6 ++---
src/test/regress/expected/sqljson.out              | 26 +++++++++++-----------
4 files changed, 19 insertions(+), 19 deletions(-)