[Dovecot] Do not keep persistent logs in a container

data/Dockerfiles/dovecot/supervisord.conf

@@ -3,19 +3,16 @@ nodaemon=true
 
 [program:syslog-ng]
 command=/usr/sbin/syslog-ng --foreground --no-caps
-redirect_stderr=true
+stdout_logfile=/dev/stdout
+stdout_logfile_maxbytes=0
+stderr_logfile=/dev/stderr
+stderr_logfile_maxbytes=0
 autostart=true
-stdout_syslog=true
 
 [program:dovecot]
 command=/usr/local/sbin/dovecot -F
 autorestart=true
 
-[program:logfiles]
-command=/usr/bin/tail -f /var/log/combined.log
-stdout_logfile=/dev/fd/1
-stdout_logfile_maxbytes=0
-
 [program:cron]
 command=/usr/sbin/cron -f
 autorestart=true

data/Dockerfiles/dovecot/syslog-ng.conf

@@ -13,9 +13,8 @@ source s_src {
   unix-stream("/dev/log");
   internal();
 };
-
-destination d_combined { file("/var/log/combined.log"); };
-destination d_redis_persistent_log {
+destination d_stdout { pipe("/dev/stdout"); };
+destination d_redis_ui_log {
   redis(
     host("redis-mailcow")
     persist-name("redis1")
@@ -34,8 +33,8 @@ destination d_redis_f2b_channel {
 filter f_mail { facility(mail); };
 log {
   source(s_src);
-  destination(d_combined);
+  destination(d_stdout);
   filter(f_mail);
-  destination(d_redis_persistent_log);
+  destination(d_redis_ui_log);
   destination(d_redis_f2b_channel);
 };