pgsql: pg_dump: Allow pg_dump to dump the statistics for foreign tables

pg_dump: Allow pg_dump to dump the statistics for foreign tables.

Commit 1fd1bd87101 introduced support for dumping statistics with
pg_dump and pg_dumpall, covering tables, materialized views, and indexes.
However, it overlooked foreign tables, even though functions like
pg_restore_relation_stats() support them.

This commit fixes that oversight by allowing pg_dump and pg_dumpall
to include statistics for foreign tables.

Author: Fujii Masao <masao(dot)fujii(at)gmail(dot)com>
Reviewed-by: Corey Huinker <corey(dot)huinker(at)gmail(dot)com>
Reviewed-by: Nathan Bossart <nathandbossart(at)gmail(dot)com>
Discussion: https://postgr.es/m/[email protected]

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/c2e2589ab969eb802493191c79de844bf7dc3a6e

Modified Files
--------------
doc/src/sgml/ref/pg_dump.sgml | 7 ++++---
doc/src/sgml/ref/pg_dumpall.sgml | 3 ++-
src/bin/pg_dump/pg_dump.c | 4 +++-
3 files changed, 9 insertions(+), 5 deletions(-)