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.  Rearrange the code a bit to
fix that.

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

discovered by John Naylor <jcnaylor@gmail.com> via scan-build

ideas and review by Tom Lane

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/4c6744ed705df6f388371d044b87d1b4a60e9f80

Modified Files
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src/pl/plpython/plpy_spi.c | 17 +++++++++++------
1 file changed, 11 insertions(+), 6 deletions(-)