pgsql: Fix overrun when comparing with unterminated ICU language string

Fix overrun when comparing with unterminated ICU language string.

The overrun was introduced in commit c4ff35f10.

Author: Andreas Karlsson <andreas@proxel.se>
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/96d80a47-f17f-42fa-82b1-2908efbd6541@gmail.com
Backpatch-through: 18

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/06ce97b9994eca91250d7c28f0df9b1ae7829f36

Modified Files
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src/backend/utils/adt/pg_locale_icu.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)