Documentation is missing some SMTP configuration

Gitlab SMTP configuration does not talk about how to turn off SSL https://docs.gitlab.com/omnibus/settings/smtp.html

Our local mail server does not have any authentication and does not support SSL. Following configuration always resulted in : OpenSSL::SSL::SSLError: SSL_connect returned=1 errno=0 state=unknown state: unknown protocol

gitlab_rails['smtp_address'] = "smtp.example.com"
gitlab_rails['smtp_port'] = 25
gitlab_rails['smtp_user_name'] = "gitlab@example.com"
gitlab_rails['smtp_domain'] = "example.com"
gitlab_rails['smtp_authentication'] = "none"
gitlab_rails['smtp_enable_starttls_auto'] = false
gitlab_rails['smtp_tls'] = false

turning off SSL like this worked

gitlab_rails['smtp_enable'] = true;
gitlab_rails['smtp_address'] = 'smtp.example.com';
gitlab_rails['smtp_port'] = 25;
gitlab_rails['smtp_domain'] = 'example.com';
gitlab_rails['gitlab_email_from'] = 'gitlab@example.com';
gitlab_rails['smtp_tls'] = false;
gitlab_rails['smtp_openssl_verify_mode'] = 'none'
gitlab_rails['smtp_enable_starttls_auto'] = false
gitlab_rails['smtp_ssl'] = false
gitlab_rails['smtp_force_ssl'] = false