postfix: Disable STARTTLS Submission (port 587)

Implicit TLS is the future[1].

[1] https://datatracker.ietf.org/doc/html/rfc8314

roles/postfix/tasks/main.yml

@@ -107,7 +107,6 @@
   ansible.posix.firewalld: service={{ item }} permanent=true state=enabled immediate=yes
   with_items:
     - smtp
-    - smtp-submission
     - smtps
   when: postfix_smtpd_public and configure_firewall
   tags:

roles/postfix/templates/master.cf.j2

@@ -24,13 +24,6 @@ localhost:smtp      inet  n       -       n       -       -       smtpd
 {% if postfix_server %}
 msa_cleanup unix n      -       n       -       0       cleanup
     -o header_checks=pcre:/etc/postfix/msa_header_checks
-submission inet n       -       n       -       -       smtpd
-    -o cleanup_service_name=msa_cleanup
-    -o syslog_name=postfix/submission
-    -o smtpd_tls_security_level=encrypt
-    -o smtpd_sasl_auth_enable=yes
-    -o smtpd_recipient_restrictions=$submission_recipient_restrictions
-    -o smtpd_client_connection_count_limit=10
 submissions inet n       -       n       -       -       smtpd
     -o cleanup_service_name=msa_cleanup
     -o smtpd_tls_wrappermode=yes

roles/prometheus/defaults/main.yml

@@ -60,5 +60,4 @@ blackbox_targets:
     - coc.archlinux.org:443
   smtp_starttls:
     - mail.archlinux.org:25
-    - mail.archlinux.org:587
     - lists.archlinux.org:25