Webhook reporting always sends DEBUG

[Andy Castille]

Configuration excerpt:

```
#cloud-config
autoinstall:
  version: 1
  # ...
  reporting:
    central:
      type: webhook
      level: INFO
      endpoint: http://192.168.2.217:58000/osInstallReport
```

Despite being configured with `level: INFO`, the endpoint receives DEBUG messages as well. This happens whether or not the INFO level is specified (which, according to the docs*, is the default, so DEBUG messages shouldn't be sent in either scenario).

For now I can filter them out on the receiving server, but as the server is not on the local network, this is a lot of internet traffic I would like to avoid.

This seems to be confirmed for another user at the end of this answer: https://askubuntu.com/a/1339595

* https://curtin.readthedocs.io/en/latest/topics/reporting.html#webhook-reporter