pgsql: dict_synonym.c: remove incorrect outlen.

dict_synonym.c: remove incorrect outlen.

Previously, outlen was miscalculated if case_sensitive was false and
str_tolower() changed the byte length of the string. If outlen was too
large, pnstrdup() would stop at the NUL terminator, preventing
overrun. But if outlen was too small, it would cause truncation.

Fix by just removing outlen. It was only used in a single site, which
could just as well use pstrdup().

Discussion: https://postgre.es/m/1101e1a3afbbabb503317069c40374b82e6f4cac.camel@j-davis.com
Reviewed-by: Tristan Partin <tristan(at)partin(dot)io>
Backpatch-through: 14

Branch
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REL_18_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/89e6484985280b259a2346b4b4805750cf6ac0ce

Modified Files
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src/backend/tsearch/dict_synonym.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)