Unable to send email to multiple senders using s-nail

Issue

• Unable to send email to multiple senders using s-nail.

• Using the s-nail command, sending to a single recipient works as expected, but it fails when attempting to send to multiple recipients.

   $ s-nail -s "Test Email Subject rhel9" test1,test2 < /dev/null
   s-nail: Null message body; hope that's ok
   s-nail: test1,test2 contains invalid byte ','
   s-nail: No recipients specified
   s-nail: ... message not sent