nixos/opensmtpd: fix opensmtpd-rspamd test

              "${pkgs.dovecot}/libexec/dovecot/deliver -d %{user.username}"

            match from any for local action dovecot_deliver

            action do_relay relay

            # DO NOT DO THIS IN PRODUCTION!

            # Setting up authentication requires a certificate which is painful in

            # a test environment, but THIS WOULD BE DANGEROUS OUTSIDE OF A

            # WELL-CONTROLLED ENVIRONMENT!

            match from any for any action do_relay

            action relay_smtp2 relay host "smtp://192.168.1.2"

            match from any for any action relay_smtp2

          '';

        };

        services.dovecot2 = {

              import smtplib, sys

              with smtplib.SMTP('192.168.1.1') as smtp:

                smtp.sendmail('alice@[192.168.1.1]', 'bob@[192.168.1.2]', """

                smtp.sendmail('alice@smtp1', 'bob@smtp2', """

                  From: alice@smtp1

                  To: bob@smtp2

                  Subject: Test