Manual invocation of wait-online error

There may be cases where `systemd-networkd-wait-online.service` is known to fail and timeout. These failures may be unrelated to cloud-init, but now that cloud-init is invoking the service directly, any failures of this service are currently causing an exit 1 from cloud-init.

```
2025-03-04 23:01:12,259 - ubuntu.py[ERROR]: Failed to wait for network: Unexpected error while running command.
Command: ['systemctl', 'start', 'systemd-networkd-wait-online.service']
Exit code: 1
Reason: -
Stdout:
Stderr: Job for systemd-networkd-wait-online.service failed because the control process exited with error code.
See "systemctl status systemd-networkd-wait-online.service" and "journalctl -xeu systemd-networkd-wait-online.service" for details.
```

We may want to downgrade this error to DEBUG, but that doesn't feel entirely right to me either.