For #28000
We started seeing errors in one of our mail tests do to an EOF being
received from the mail client when sending the QUIT command. This should
be non-fatal (the mail should already have been sent) and it can happen
especially in localhost scenarios where things move very fast, and the
mail server closes the connection before we have a chance to send QUIT.
It's not clear why it started failing consistently when it did; I tried
[reverting the commit after the last known good
run](https://github.com/fleetdm/fleet/pull/27989) and it had no effect.
Scott Gress
393abd1461