Mail-receiver log errors after letsencrypt update

Support
6

I believe I figured this one out, there is a maillog_file line missing in the Dockerfile. Temp fix: added

  POSTCONF_maillog_file: '/dev/stdout'

to mail-receiver.yml and rebuilt, but this should probably be fixed in the docker image

RUN >/etc/postfix/main.cf \
+	&& postconf -e maillog_file=/dev/stdout \
	&& postconf -e smtputf8_enable=no \
...