pgsql: Initialize new jsonb iterator to zero

Initialize new jsonb iterator to zero

Use palloc0() instead of palloc() to create a new JsonbIterator.
Otherwise, the isScalar field is sometimes not initialized.  There is
probably no impact in practice, but it's cleaner this way and it avoids
future problems.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/3c9cf069454d80b0b4a54a0a90941a88a97b1122

Modified Files
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src/backend/utils/adt/jsonb_util.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)