[Dovecot] Remove last_login, fixes #4121

data/conf/dovecot/dovecot.conf

@@ -482,8 +482,6 @@ plugin {
   acl_anyone = </etc/dovecot/acl_anyone
   acl_shared_dict = file:/var/vmail/shared-mailboxes.db
   acl = vfile
-  last_login_dict = </etc/dovecot/last_login
-  last_login_key = last-login/%s/%u
   fts = solr
   fts_autoindex = yes
   fts_solr = url=http://solr:8983/solr/dovecot-fts/