update nixpkgs and some host config

flake.lock

hosts/elrond/strongswan.nix

hosts/elros/default.nix

hosts/maura/links.nix

modules/kloenk/strongswan/default.nix

pkgs/evremap/default.nix

services/knot-dns/primary/zones/common.nix

services/knot-dns/primary/zones/de.kloenk.nix

services/knot-dns/primary/zones/dev.kloenk.nix

services/knot-dns/primary/zones/eu.kloenk.nix

services/monitoring/prometheus-rules.nix

services/monitoring/prometheus.nix