pgsql: Fix intermetent test failure in 028_row_filter.pl.

Fix intermetent test failure in 028_row_filter.pl.

The test was not waiting for the subscriber's data synchronization to
happen after refreshing the publication on the subscriber side. This leads
subscriber's apply worker to skip applying the changes on the
corresponding relation which results in a test failure.

Reported-by: Hou Zhijie, as per buildfarm
Author: Hou Zhijie
Reviewed-by: Masahiko Sawada, Amit Kapila
Discussion: https://postgr.es/m/OS0PR01MB5716A69496A8E2F2E155DB8D94B59@OS0PR01MB5716.jpnprd01.prod.outlook.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/1f50918a6fb02207d151e7cb4aae4c36de9d827c

Modified Files
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src/test/subscription/t/028_row_filter.pl | 5 +++++
1 file changed, 5 insertions(+)