This bug was fixed in the package sendmail - 8.15.2-11ubuntu1
--------------- sendmail (8.15.2-11ubuntu1) cosmic; urgency=medium
* Fix "update-inetd: error: --group is only relevant with --add" by removing the --group argument where it's irrelevant. (LP: #1792582)
-- Brian Murray <email address hidden> Fri, 19 Oct 2018 16:21:45 -0700
This bug was fixed in the package sendmail - 8.15.2-11ubuntu1
---------------
sendmail (8.15.2-11ubuntu1) cosmic; urgency=medium
* Fix "update-inetd: error: --group is only relevant with --add" by removing
the --group argument where it's irrelevant. (LP: #1792582)
-- Brian Murray <email address hidden> Fri, 19 Oct 2018 16:21:45 -0700