pgsql: Fix check on test function's arguments

Fix check on test function's arguments

The function won't cope with nkinds == 0, it leads to division by
zero. It's just a test function though, so this is harmless and
there's no need to backport.

Author: Yuriy Grigoryev <ju(dot)grigorev(at)ftdata(dot)ru>
Reviewed-by: Sho Ito <i(dot)sho(dot)0628(at)gmail(dot)com>
Discussion: https://www.postgresql.org/message-id/1905e9d709554733b418d06a4806436f@localhost.localdomain

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/5f36942fd3196259ad5ad691f5ecbe4ce555ab7c

Modified Files
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src/test/modules/test_resowner/test_resowner_many.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)