pgsql: Fix memory leaks in px_crypt_shacrypt().

Fix memory leaks in px_crypt_shacrypt().

Per Coverity. I don't think these are of any actual significance
since the function ought to be invoked in a short-lived context.
Still, if it's trying to be neat it should get it right.

Also const-ify a constant and fix up typedef formatting.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/8ab6ef2bb8d9a00d205742932eb0b6daf62b34e0

Modified Files
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contrib/pgcrypto/crypt-sha.c | 16 ++++++++--------
src/tools/pgindent/typedefs.list | 1 +
2 files changed, 9 insertions(+), 8 deletions(-)