pgsql: Improve one of the test cases in 035_standby_logical_decoding.pl

Improve one of the test cases in 035_standby_logical_decoding.pl.

The test to ensure that decoding changes via logical slot from another
database will fail was incorrectly done on the primary node instead of on
the standby node.

In the passing, make the test to wait for replay catchup by using
wait_for_replay_catchup(). This will make it consistent with the way we
wait at other places in the test.

Author: Shi yu
Reviewed-by: Bertrand Drouvot, Amit Kapila
Discussion: https://postgr.es/m/OSZPR01MB6310B0A507A0F2A2D379F38CFD6A9@OSZPR01MB6310.jpnprd01.prod.outlook.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/4d26d93ff7fbf7bde5710595255ca9c8033a1402

Modified Files
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src/test/recovery/t/035_standby_logical_decoding.pl | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)