Email domains with DMARC protection are forwarded

[Dan Kortschak]

When a bug report is filed the report is sent to the reporter in addition to the other bug subscribers. When I filed a bug today I noticed that I received no copy of my report. Looking in my spam folder, I find the email in question. This is explained by the fact that I have DMARC protection on my email domain and launchpad does a direct forward using my email address. This results in a DMARC report that looks something like this:

```
  <record>
    <row>
      <source_ip>91.189.90.7</source_ip>
      <count>10</count>
      <policy_evaluated>
        <disposition>quarantine</disposition>
        <dkim>fail</dkim>
        <spf>fail</spf>
      </policy_evaluated>
    </row>
    <identifiers>
      <header_from>real.domain</header_from>
    </identifiers>
    <auth_results>
      <spf>
        <domain>canonical.com</domain>
        <result>none</result>
      </spf>
    </auth_results>
  </record>
```

... and so a quarantine. This is not ideal (though better than if I had specified p=reject). Perhaps launchpad could send From: itself?