FIX: Use example domain in mail receiver example config

FIX: Use example domain in mail receiver example config

Context at Clarification needed in Direct email delivery setup instructions - #4 by pfaffman - support - Discourse Meta

Co-authored-by: Jay Pfaffman jay@literatecomputing.com

diff --git a/samples/mail-receiver.yml b/samples/mail-receiver.yml
index 1a3d11b..df5e3cd 100644
--- a/samples/mail-receiver.yml
+++ b/samples/mail-receiver.yml
@@ -22,7 +22,7 @@ env:
   ## to use the same domain as the forum itself here.
   MAIL_DOMAIN: discourse.example.com
 # uncomment these (and the volume below!) to support TLS 
-#  POSTCONF_smtpd_tls_key_file:  /letsencrypt/discourse.example.com/prop.ltcmp.net.key
+#  POSTCONF_smtpd_tls_key_file:  /letsencrypt/discourse.example.com/discourse.example.com.key
 #  POSTCONF_smtpd_tls_cert_file:  /letsencrypt/discourse.example.com/fullchain.cer
 #  POSTCONF_smtpd_tls_security_level: may
 

GitHub sha: 8d1b64de325c82bcf9395f583ac67462e001d50e

This commit appears in #559 which was approved by eviltrout. It was merged by Falco.