pgsql: Fix the unstable output of tests added by commit 8fccf75834.

Fix the unstable output of tests added by commit 8fccf75834.

The test cases added by that commit were trying to test the exact number of
times a particular transaction has spilled. However, that number can vary if
any background transaction (say by autovacuum) happens in parallel to the main
transaction. So let's not try to verify the exact count.

Author: Amit Kapila
Reviewed-by: Sawada Masahiko
Discussion: https://postgr.es/m/CA+fd4k5_pPAYRTDrO2PbtTOe0eHQpBvuqmCr8ic39uTNmR49Eg@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/2050832d0d637358a376a99514071941aa93ed31

Modified Files
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contrib/test_decoding/expected/stats.out | 20 +++++++++++---------
contrib/test_decoding/sql/stats.sql      | 12 +++++++-----
2 files changed, 18 insertions(+), 14 deletions(-)