Exception when no activator found

On FreeBSD system:

2021-10-24 14:00:10,707 - util.py[WARNING]: failed stage init
failed run of stage init
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Traceback (most recent call last):
  File "/usr/local/lib/python3.8/site-packages/cloudinit/cmd/main.py", line 682, in status_wrapper
    ret = functor(name, args)
  File "/usr/local/lib/python3.8/site-packages/cloudinit/cmd/main.py", line 391, in main_init
    init.apply_network_config(bring_up=bool(mode != sources.DSMODE_LOCAL))
  File "/usr/local/lib/python3.8/site-packages/cloudinit/stages.py", line 824, in apply_network_config
    return self.distro.apply_network_config(
  File "/usr/local/lib/python3.8/site-packages/cloudinit/distros/__init__.py", line 230, in apply_network_config
    network_activator = activators.select_activator()
  File "/usr/local/lib/python3.8/site-packages/cloudinit/net/activators.py", line 274, in select_activator
    raise RuntimeError(
RuntimeError: No available network activators found. Searched through list: [<class 'cloudinit.net.activators.IfUpDownActivator'>, <class 'cloudinit.net.activators.NetworkManagerActivator'>, <class 'cloudinit.net.activators.NetplanActivator'>, <class 'cloudinit.net.activators.NetworkdActivator'>]
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Given that there are additional network management tools that we haven't yet supported with activators, we should log a warning and continue without network activation here, especially since this was a no-op for years.