Messages from firebase-oss-bot@ossbot.computer always land in my spam folder

I presume this is related to

```
ARC-Authentication-Results: i=1; mx.google.com;
dkim=permerror (no key for signature) header.i=@mail.ossbot.computer header.s=pic header.b=ErXb5OLE;
spf=none (google.com: bounce+e501b9.0ca6c-firebase-android-eng=google.com@mail.ossbot.computer does not designate permitted sender hosts) smtp.mailfrom="bounce+e501b9.0ca6c-firebase-android-eng=google.com@mail.ossbot.computer"
Received: from m43-11.mailgun.net (m43-11.mailgun.net. [69.72.43.11])
by mx.google.com with UTF8SMTPS id af79cd13be357-7c7a1412f3dsi127675585a.314.2025.04.09.10.00.15
for
(version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128);
Wed, 09 Apr 2025 10:00:16 -0700 (PDT)
Received-SPF: none (google.com: bounce+e501b9.0ca6c-firebase-android-eng=google.com@mail.ossbot.computer does not designate permitted sender hosts) client-ip=69.72.43.11;
```

Looks like [something](http://go/email-hardening-workflow#3rd-party-senders) needs to be [configured in Mailgun](https://www.mailgun.com/blog/deliverability/implement-dmarc/).