add Date: and Message-Id: headers for "F-Secure: New device login" e-mails

fantomas

the e-mails notifying about login from new device don't contain headers like Date: and Message-Id.

Missing Date: makes it hard to find out when the mail was sent...

I can find it in the Recevied header, but any mail client I access the e-mail from will by default assume the mail may be hours/days old

Received: from ip-10-112-43-29.ew1-prd.service-discovery.fsapi.com (unknown [10.112.43.29])
	by mailgw.eu-west-1.ele.fsapi.com (Postfix) with ESMTPS id 1D044400E6
	for <uhlar@nextra.sk>; Mon,  6 Sep 2021 16:27:05 +0000 (UTC)
Mime-Version: 1.0
Content-Type: multipart/alternative; boundary="=_t04-18811-1630945625-0001-2"
Subject: F-Secure: New device login
From: F-Secure <no-reply@f-secure.com>