Fix formatting of description of systemd command

When running "podman-compose", the list of commands gets displayed.
The systemd command is an outlier, showing multiple lines, IMO
unintended at this location.

This change moves the longer command description to its proper place,
that is, it gets shown when "podman-compose systemd --help" is
executed.

Signed-off-by: Cleber Rosa <crosa@redhat.com>

podman_compose.py

@@ -1606,7 +1606,7 @@ def _parse_args(self):
  _ = subparsers.add_parser("help", help="show help")
  for cmd_name, cmd in self.commands.items():
  subparser = subparsers.add_parser(
- cmd_name, help=cmd.desc
+ cmd_name, help=cmd.help, description=cmd.desc
  ) # pylint: disable=protected-access
  for cmd_parser in cmd._parse_args: # pylint: disable=protected-access
  cmd_parser(subparser)
@@ -1713,7 +1713,13 @@ def wrapped(*args, **kw):
 
  wrapped._compose = self.compose
  # Trim extra indentation at start of multiline docstrings.
- wrapped.desc = self.cmd_desc or re.sub(r"^\s+", "", func.__doc__)
+ help_desc = self.cmd_desc or re.sub(r"^\s+", "", func.__doc__)
+ if "\n" in help_desc:
+ wrapped.help, wrapped.desc = help_desc.split("\n", 1)
+ else:
+ wrapped.help = help_desc
+ wrapped.desc = None
+
  wrapped._parse_args = []
  self.compose.commands[self.cmd_name] = wrapped
  return wrapped