mkosi: Support running systemd-networkd-tests.py in QEMU

This commit adds the necessary packages for Fedora and Arch.

mkosi.default.d/arch/10-mkosi.arch

@@ -63,3 +63,8 @@ Packages=
         # For testing systemd's zsh completion scripts
         # Run `autoload -Uz compinit; compinit` from a zsh shell in the booted image to enable completions.
         zsh
+        # Required to run systemd-networkd-tests.py
+        iproute
+        dnsmasq
+        wireguard-tools
+        dhcp

mkosi.default.d/fedora/10-mkosi.fedora

@@ -75,3 +75,10 @@ Packages=
         netcat
         e2fsprogs
         compsize
+        # Required to run systemd-networkd-tests.py
+        iproute
+        iproute-tc
+        dnsmasq
+        wireguard-tools
+        dhcp-server
+        kernel-modules-extra

test/test-network/systemd-networkd-tests.py

@@ -5,6 +5,9 @@
 # pylint: disable=missing-function-docstring,missing-class-docstring,missing-module-docstring
 # systemd-networkd tests
 
+# These tests can be executed in the systemd mkosi image when booted in QEMU. After booting the QEMU VM,
+# simply run this file which can be found in the VM at /root/src/test/test-network/systemd-networkd-tests.py.
+
 import argparse
 import errno
 import itertools