pgsql: Remove useless pstrdup() calls.

Remove useless pstrdup() calls.

The result of PLyUnicode_AsString is already palloc'd,
so pstrdup'ing it is just a waste of time and memory.
More importantly it might confuse people about whether
that's necessary. Doesn't seem important enough to
back-patch, but we should fix it. Spotted by Coverity.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/716c451128a141acbae1ccab6946c716021a977f

Modified Files
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src/pl/plpython/plpy_elog.c | 2 +-
src/pl/plpython/plpy_plpymodule.c | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)