pgsql: pgstat: test stats interactions with physical replication.

pgstat: test stats interactions with physical replication.

Tests that standbys:
- drop stats for objects when the those records are replayed
- persist stats across graceful restarts
- discard stats after immediate / crash restarts

Author: Melanie Plageman <melanieplageman@gmail.com>
Author: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/20220303021600.hs34ghqcw6zcokdh@alap3.anarazel.de

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/53b9cd20d4144f5d65c107babe23916aad6c2ef8

Modified Files
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src/test/recovery/t/030_stats_cleanup_replica.pl | 206 +++++++++++++++++++++++
1 file changed, 206 insertions(+)