Обсуждение: pgsql: Clarify documentation for the initcap function

Clarify documentation for the initcap function

This commit documents differences in the definition of word separators for
the initcap function between libc and ICU locale providers.
Backpatch to all supported branches.

Discussion: https://postgr.es/m/804cc10ef95d4d3b298e76b181fd9437%40postgrespro.ru
Author: Oleg Tselebrovskiy <o.tselebrovskiy@postgrespro.ru>
Backpatch-through: 13

Branch
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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/d861b9282261b066a1147d920a27527c22dc499d

Modified Files
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doc/src/sgml/func.sgml | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)