pgsql: Add test for pg_recvlogical reconnection behavior.

Add test for pg_recvlogical reconnection behavior.

This commit adds a test to verify that data already received and flushed by
pg_recvlogical is not streamed again even after the connection is lost,
reestablished, and logical replication is restarted.

Author: Mircea Cadariu <cadariu(dot)mircea(at)gmail(dot)com>
Co-authored-by: Fujii Masao <masao(dot)fujii(at)gmail(dot)com>
Reviewed-by: Chao Li <li(dot)evan(dot)chao(at)gmail(dot)com>
Discussion: https://postgr.es/m/CAHGQGwFeTymZQ7RLvMU6WuDGar8bUQCazg=VOfA-9GeBkg-FzA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/d89b1d817513025e2c1f821090c4262fcedf5be2

Modified Files
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src/bin/pg_basebackup/t/030_pg_recvlogical.pl | 94 +++++++++++++++++++++++++++
1 file changed, 94 insertions(+)