Adjust env comment for all supported options

Author: adamgilbert

.env

@@ -48,7 +48,7 @@ POSTFIX_RELAYHOST_PORT=587
 POSTFIX_SASL_AUTH=
 POSTFIX_TLS=
 
-# Configure docker log driver - currently supports 'none', 'syslog' or 'journald'
+# Configure docker log driver - currently supports 'none', 'syslog' or 'journald' or 'json-file' (assuming no tags)
 LOG_DRIVER=json-file
 
 # Configure the moodle backup path