python3-nose [has been removed from Debian Trixie](https://tracker.debian.org/news/1622886/nose-removed-from-testing/) and is superseded by [python3-nose2](https://packages.debian.org/trixie/amd64/python3-nose2), which is also [available in Bookworm](https://packages.debian.org/bookworm/amd64/python3-nose2).
It appears to be fully compatible with the older nose.
The change can be imported from https://github.com/vyos/vyos-build/pull/978/commits/d9424bf64001725d4b3376c908f2ea070b659933