pgsql: Tidy up after incremental JSON parser patch

Tidy up after incremental JSON parser patch

Remove junk left over from non-vpath builds.

Try to remedy gettext error on some platforms.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/88620824c2a62376e224c4b595b9fe69fb858978

Modified Files
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src/common/jsonapi.c                         | 4 ++--
src/test/modules/test_json_parser/.gitignore | 3 +++
src/test/modules/test_json_parser/Makefile   | 5 +++++
3 files changed, 10 insertions(+), 2 deletions(-)