net-mgmt/collectd5: Chase 31418910e0f4, update sysutils/nut to 2.8.0

Nut upsclient.h no longer includes time.h. Apps which build against
upsclient.h must now include time.h or fail to detect nut libraries
due to missing time_t.

PR: 263791
Reported by: Petteri Valkonen <petteri.valkonen@iki.fi>