pgsql: Add a TAP test for test_json_parser_perf

Add a TAP test for test_json_parser_perf

This just makes sure the test can run with a single iteration. A real
performance test would test with many more.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/daf554dbeabf0957a25c9e37488d42c047c0ce23

Modified Files
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src/test/modules/test_json_parser/meson.build | 3 +-
.../test_json_parser/t/004_test_parser_perf.pl | 35 ++++++++++++++++++++++
2 files changed, 37 insertions(+), 1 deletion(-)