[V3 Core] More features for the bot invite URL (#1847)

* Add inviteset group command

* Fix errors

* Fix line break

* Remove user bot support

* Fix docstrings line breaks

* Remove embed specific formatting

* Remove invite redirect

* Add self argument to _can_get_invite_url

* Remove unused import

* fix errors related to classes + double help

* Removed self bot support

redbot/core/bot.py

@@ -60,6 +60,8 @@ class RedBase(commands.GroupMixin, commands.bot.BotBase, RPCMixin):  # pylint: d
             help__verify_checks=True,
             help__verify_exists=False,
             help__tagline="",
+            invite_public=False,
+            invite_perm=0,
             disabled_commands=[],
             disabled_command_msg="That command is disabled.",
             api_tokens={},