pgsql: doc: Fix datatype for postgres_fdw option

doc: Fix datatype for postgres_fdw option

The datatype for analyze_sampling had accidentally been set to text
and not string.  Backpatch to v16 where analyze_sampling first was
introduced.

Author: Shinya Kato <Shinya11.Kato@oss.nttdata.com>
Reviewed-by: Laurenz Albe <laurenz.albe@cybertec.at>
Discussion: https://postgr.es/m/7fd9166b9fda267411793f39986d7f24@oss.nttdata.com
Backpatch-through: v16

Branch
------
master

Details
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https://git.postgresql.org/pg/commitdiff/0cf79a7f6801d3e69de6450d585e385a4064b057

Modified Files
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doc/src/sgml/postgres-fdw.sgml | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)