pgsql: psql: Fix tab completion for DROP INDEX CONCURRENTLY

psql: Fix tab completion for DROP INDEX CONCURRENTLY

psql offered CASCADE after DROP INDEX CONCURRENTLY and an index name,
even though CASCADE is not supported with CONCURRENTLY. Offer only
RESTRICT in this case, while retaining both CASCADE and RESTRICT
for ordinary DROP INDEX.

Backpatch to all supported versions.

Author: Sho Ito <i(dot)sho(dot)0628(at)gmail(dot)com>
Reviewed-by: Chao Li <li(dot)evan(dot)chao(at)gmail(dot)com>
Reviewed-by: Shihao Zhong <zhong950419(at)gmail(dot)com>
Reviewed-by: Fujii Masao <masao(dot)fujii(at)gmail(dot)com>
Discussion: https://postgr.es/m/CAG7L5+7KXgvJUGCGXzyQrt7UysC9iytaYzx-7YyQTFYXjHVTWQ@mail.gmail.com
Backpatch-through: 14

Branch
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REL_19_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/a19c3f36b3df51be3ad257c51312e8261675546a

Modified Files
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src/bin/psql/tab-complete.in.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)