I've seen MySQL tested against power outages and hardware failure on a dozen occasions. If I got paid overtime for dealing with the results I'd probably own half of Vancouver by now.
Do they do it for every release? What about OOM error testing? IO error tests? fuzz tests? UB tests? Fuzz tests? Malformed DB tests? Valgrind analysis? Memory leak checking? Regression tests?
SQLite does all of that and more with every release (https://sqlite.org/testing.html). There's a reason I consider their test coverage impressive...