Thread: pgsql: Refactor/reword some error messages to avoid duplicates

Refactor/reword some error messages to avoid duplicates

Also, remove brackets around "EMPTY [ ARRAY ]".  An error message is
not the place to state that a keyword is optional.

Backpatch to 17.

Branch
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REL_17_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/899f39ea25f2ee63a0c557f3908e15b280a4367a

Modified Files
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src/backend/executor/execExprInterp.c            |  8 ++-
src/backend/parser/parse_expr.c                  | 90 +++++++++++++++++-------
src/backend/parser/parse_jsontable.c             |  4 +-
src/test/regress/expected/sqljson_jsontable.out  |  4 +-
src/test/regress/expected/sqljson_queryfuncs.out |  2 +-
5 files changed, 74 insertions(+), 34 deletions(-)