By default, nothing differentiates errors or fatals from regular logs, so they just
blend into the rest of the logs.
As a bonus, if you run a test using t.Run(), the log messages printed
via the sub-t.Run() are printed at a different time from log messages
printed via the parent t.Run(), making debugging almost impossible.
This doesn't actually fix the test flake I'm looking for, but at least
I can find it in the logs now.
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>