pgsql: pgstat: add tests for handling of restarts, including crashes.

pgstat: add tests for handling of restarts, including crashes.

Test that stats are restored during normal restarts, discarded after a crash /
immediate restart, and that a corrupted stats file leads to stats being reset.

Author: Melanie Plageman <melanieplageman@gmail.com>
Author: Andres Freund <andres@anarazel.de>
Discussion: /messages/by-id/20220303021600.hs34ghqcw6zcokdh@alap3.anarazel.de

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/16acf7f1aaea6c5efc0fa49182c16cd6bfd9f3d3

Modified Files
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src/test/recovery/t/029_stats_restart.pl | 307 +++++++++++++++++++++++++++++++
1 file changed, 307 insertions(+)