Merge branch '5810-check-mailman-paths-on-centos-8' into 'develop'

Resolve "Check mailman paths on CentOS 8"

Closes #5810

See merge request ispconfig/ispconfig3!1264

Author: Till Brehm

install/tpl/fedora_postfix.conf.master

@@ -1,5 +1,5 @@
 virtual_alias_domains = proxy:mysql:{config_dir}/mysql-virtual_alias_domains.cf
-virtual_alias_maps = hash:/var/lib/mailman/data/virtual-mailman, proxy:mysql:{config_dir}/mysql-virtual_forwardings.cf, proxy:mysql:{config_dir}/mysql-virtual_alias_maps.cf, proxy:mysql:{config_dir}/mysql-virtual_email2email.cf
+virtual_alias_maps = hash:/etc/mailman/virtual-mailman, proxy:mysql:{config_dir}/mysql-virtual_forwardings.cf, proxy:mysql:{config_dir}/mysql-virtual_alias_maps.cf, proxy:mysql:{config_dir}/mysql-virtual_email2email.cf
 virtual_mailbox_domains = proxy:mysql:{config_dir}/mysql-virtual_domains.cf
 virtual_mailbox_maps = proxy:mysql:{config_dir}/mysql-virtual_mailboxes.cf
 virtual_mailbox_base = {vmail_mailbox_base}