pgsql: PL/Python: Fix potential NULL pointer dereference

PL/Python: Fix potential NULL pointer dereference

After d0aa965c0a0ac2ff7906ae1b1dad50a7952efa56, one error path in
PLy_spi_execute_fetch_result() could result in the variable "result"
being dereferenced after being set to NULL.  To fix that, just clear the
resources right there and return early.

Also add another SPI_freetuptable() call so that that is cleared in all
error paths.

discovered by John Naylor  via scan-build

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/e42e2f38907681c48c43f49c5ec9f9f41a9aa9a5

Modified Files
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src/pl/plpython/plpy_spi.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)