[Audio] Allow a custom voice room to be specified in the arguments to the summon command.

[AAA3A-AAA3A]

Description of the changes

Hello,
With this code, a user will be able to use the summon command like this: [p]summon id_or_mention.
Some users will be able to put the bot in when it starts up, without having to join a chat room.
Of course, users should be careful with "empty disconnect". Otherwise, it will work.
Thank you in advance.

[Drapersniper]

While this is not standard - usually discord clients allow users to reference text channels this is not the case for Voice channels which means users are required to explicitly use the channel ID.

Functionaly the PR is sound.

You need to address the changes I suggested - Optional without an a default hides the arguments in our Help.

When making PRs make sure to run make reformat in the root folder of the project to apply black -l 99 to all files changed.

In addition to the above you will need to update the docstrings for this command (Currently just """Summon the bot to a voice channel.""") to mention that users will need to use the channel ID - with a link to the documentation of where/how to get that.
And the difference in behaviour if a channel ID is not used.

@aikaterna please request changes (I'm unable to do so)

[AAA3A-AAA3A]

This is good. The change has been made.

[AAA3A-AAA3A]

The extra empty line has been added.

[Drapersniper]

LGTM

[AAA3A-AAA3A]

I did what you said.

[Kreusada]

Suggested change

	To learn how to get a channel ID please read the following help article: <https://support.discord.com/hc/en-us/articles/206346498-Where-can-I-find-my-User-Server-Message-ID>
	To learn how to get a channel ID please read [this help article](https://support.discord.com/hc/en-us/articles/206346498-Where-can-I-find-my-User-Server-Message-ID).

In this case, it might look more presentable to use hyperlink syntax instead of just having the link as it is (see my suggestion)

[Flame442]

The one issue with hyperlinks is that in non-embed help it renders without formatting. I can't remember if we've accepted this limitation in other commands with links in core, but if we have not I'd say to continue to not use them.