Can't use 'none' DISCOURSE_SMTP_AUTHENTICATION

[homebrewhops]

Thank you @anthony-o!!

The key was: (all other non displayed DISCOURSE_SMTP_ parameter were commented)*

DISCOURSE_SMTP_ADDRESS: my.smtp.server.tld
DISCOURSE_SMTP_PORT: 25
DISCOURSE_SMTP_AUTHENTICATION: none
DISCOURSE_SMTP_OPENSSL_VERIFY_MODE: none