dns/{knot3,py-libknot}: Update 3.5.7 => 3.5.8
Changelog:
https://www.knot-dns.cz/2026-09-04-version-358.html
PR: 298191
Reported by: Leo Vandewoestijne <freebsd@dns.company> (maintainer)
Approved by: osa, vvd (Mentors, implicit)
MFH: 2026Q3
(cherry picked from commit e39d07c0acd6010a3a6fca1e994f5333d5ce018c)