Change debug printing to log filename
When restarting the cluster fails the code introduced in
33774978c78
printed the full log contents to aid debugging. For cases when the
logfile is large this adds unnecessary overhead. Reduce to printing
the logfile path instead.
Reported-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/
20240406214439.2n4zf2w7ukhf7dsy@awork3.anarazel.de