pgsql: vacuumdb: Fix --missing-stats-only with virtual generated column

vacuumdb: Fix --missing-stats-only with virtual generated columns.

Statistics aren't created for virtual generated columns, so
"vacuumdb --missing-stats-only" always chooses to analyze tables
that have them. To fix, modify vacuumdb's query for retrieving
relations that are missing statistics to exclude those columns.

Oversight in commit edba754f05.

Author: Yugo Nagata <nagata(at)sraoss(dot)co(dot)jp>
Reviewed-by: Fujii Masao <masao(dot)fujii(at)gmail(dot)com>
Reviewed-by: Corey Huinker <corey(dot)huinker(at)gmail(dot)com>
Discussion: https://postgr.es/m/20250820104226.8ba51e43164cd590b863ce41%40sraoss.co.jp
Backpatch-through: 18

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b63952a7811319a6525a9ea23afa294a900fa895

Modified Files
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src/bin/scripts/t/100_vacuumdb.pl | 7 ++++---
src/bin/scripts/vacuumdb.c | 5 +++++
2 files changed, 9 insertions(+), 3 deletions(-)