Add restart command

[ViRb3]

For when the bot glitches out...

[lucidBrot]

What can be fixed with this that can not be fixed otherwise?
I'm not opposed, just curious.

[ViRb3]

I only ever had the bot "glitch out" once, here are the logs:

AttributeError: 'dict' object has no attribute 'id'
ERROR:discord_slash:An exception has occurred while executing command `chal`:
Traceback (most recent call last):
  File "/root/.cache/pypoetry/virtualenvs/organizers-bot-9TtSrW0h-py3.11/lib/python3.11/site-packages/discord_slash/client.py", line 872, in invoke_command
    await func.invoke(ctx, args)
  File "/root/.cache/pypoetry/virtualenvs/organizers-bot-9TtSrW0h-py3.11/lib/python3.11/site-packages/discord_slash/model.py", line 168, in invoke
    return await coro
           ^^^^^^^^^^
  File "/app/organizers_bot/bot.py", line 31, in wrapper
    return await f(ctx, *args, **kw)
           ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/app/organizers_bot/bot.py", line 90, in create_challenge_channel
    await ctfnote.add_task(ctx, created, challenge, category, solved_prefix = "✓-", ctfid = ctfid)
  File "/app/organizers_bot/ctfnote.py", line 564, in add_task
    f"<{config.ctfnote.url}#/ctf/{current_ctf.id}-{slugify(current_ctf.name)}/task/{result.id}-{slugify(result.title)}>"

I never figured out what exactly was wrong, but a restart fixed it. This PR is just in case the bot operator is not available and the players need a quick fix.

[RobinJadoul]

The glitch may have been when the ctfnote was down or some other issue happened with it, this might already be mitigated more due to some later changes that properly disable the integration

I don't expect just exit(1) will properly restart this, the way we're running it, there's no auto-restart happening atm, since the discord library makes sure everything stays alive.
I furthermore don't really think it would fully resolve underlying issues much more than the regular error handling.

For bot operator being afk, right now several people should have access to the bot server, if they remember they do. (iirc it's me, cyanpencil, nspace and spittfire).

[RobinJadoul]

If anything, probably the config reload as suggested in #12 could be more useful