...including a slightly more careful config around restarts, i.e.
* We have intervals of 5 seconds between restarts instead of 100ms.
* If we exceed 5 start attempts in 5*120s (with 120s being the timeout),
start job gets rate-limited and thus aborted. Do note that there are
at most 5 start attempts allowed in ~625s by default. If the startup
fails very quickly, either wait until the rate-limit is over or reset
the counter using `systemctl reset-failed postgresql.service`.
* The interval of 625s (plus 5s of buffer) are automatically derived
from RestartSec & TimeoutSec. Changing either will also affect
StartLimitIntervalSec unless overridden with `mkForce`.