pgsql: postgres_fdw: Fix syntax error in fetch_attstats().

postgres_fdw: Fix syntax error in fetch_attstats().

When importing remote stats for a foreign table backed by a pre-v17
remote server, the query built/executed in this function has three NULL
placeholders for the range stats supported in v17 at the end of the
SELECT list. Previously, it included a trailing comma after the last
NULL, like "SELECT ..., NULL, NULL, NULL, FROM pg_catalog.pg_stats ...",
causing a syntax error on the remote server. Fix by removing the comma.

Oversight in commit 28972b6fc.

Author: Satya Narlapuram <satyanarlapuram(at)gmail(dot)com>
Discussion: https://postgr.es/m/CAHg%2BQDdEE7wp1S60Fn9Kmna8KfdMo5Tu6dROLpMn_-EOUBKmWQ%40mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/3f7a1afbaef06a7af93223cf2a653f2ec5740590

Modified Files
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contrib/postgres_fdw/postgres_fdw.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)