pgsql: Throw a more on-point error for publications depending on column

Throw a more on-point error for publications depending on columns.

Same as 42b041243, except that the trouble case is a publication
WHERE clause that depends on a column.

Again reported by Alexander Lakhin.  Back-patch to v15 where
we added publication WHERE clauses.

Discussion: https://postgr.es/m/548a47bc-87ae-b3df-c6a2-60b9966f808b@gmail.com

Branch
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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/11d40a44ba325f254562a3fbd8ccd2791f12b9b5

Modified Files
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src/backend/commands/tablecmds.c | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)