Description of problem:
Running "dnf group info" crashes with a traceback


Version-Release number of selected component (if applicable):
$ dnf --version
4.2.8
  Installed: dnf-0:4.2.8-2.fc30.noarch at Sun Sep 15 18:09:42 2019
  Built    : Fedora Project at Tue Sep 10 12:16:53 2019

  Installed: rpm-0:4.14.2.1-5.fc30.x86_64 at Sun Sep 15 18:05:34 2019
  Built    : Fedora Project at Thu Aug 29 10:46:16 2019


How reproducible:
2/3:
I could reproduce this one my work system as well as on a freshly installed Fedora 30 VM. Both x86_64.
I could not reproduce it on Fedora 29 i686

Steps to Reproduce:
1. Start Fedora 30 x86_64
2. Open a terminal
4. sudo dnf group info


Actual results:
Traceback (most recent call last):
  File "/usr/bin/dnf", line 58, in <module>
    main.user_main(sys.argv[1:], exit_code=True)
  File "/usr/lib/python3.7/site-packages/dnf/cli/main.py", line 191, in user_main
    errcode = main(args)
  File "/usr/lib/python3.7/site-packages/dnf/cli/main.py", line 65, in main
    return _main(base, args, cli_class, option_parser_class)
  File "/usr/lib/python3.7/site-packages/dnf/cli/main.py", line 94, in _main
    cli.configure(list(map(ucd, args)), option_parser())
  File "/usr/lib/python3.7/site-packages/dnf/cli/cli.py", line 970, in configure
    self.command.configure()
  File "/usr/lib/python3.7/site-packages/dnf/cli/commands/group.py", line 339, in configure
    self.cli.optparser.print_help(self)
  File "/usr/lib/python3.7/site-packages/dnf/cli/option_parser.py", line 407, in print_help
    self._add_command_options(command)
  File "/usr/lib/python3.7/site-packages/dnf/cli/option_parser.py", line 380, in _add_command_options
    command.set_argparser(self.command_group)
  File "/usr/lib/python3.7/site-packages/dnf/cli/commands/group.py", line 313, in set_argparser
    help=_("include optional packages from group"))
  File "/usr/lib/python3.7/site-packages/dnf/cli/option_parser.py", line 384, in cmd_add_argument
    return type(self.command_group).add_argument(self.command_group, *args, **kwargs)
  File "/usr/lib64/python3.7/argparse.py", line 1367, in add_argument
    return self._add_action(action)
  File "/usr/lib64/python3.7/argparse.py", line 1571, in _add_action
    action = super(_ArgumentGroup, self)._add_action(action)
  File "/usr/lib64/python3.7/argparse.py", line 1381, in _add_action
    self._check_conflict(action)
  File "/usr/lib64/python3.7/argparse.py", line 1520, in _check_conflict
    conflict_handler(action, confl_optionals)
  File "/usr/lib64/python3.7/argparse.py", line 1529, in _handle_conflict_error
    raise ArgumentError(action, message % conflict_string)
argparse.ArgumentError: argument --with-optional: conflicting option string: --with-optional

Expected results:
mini-usage output for dnf group info

Additional info:
See also bug #1209649 for desired output