Before this change, the README included a Discord invite link using
CommonMark’s regular link syntax [1]. When a link’s text and destination
are the same, you can use an autolink [2] to avoid repeating yourself.
This change replaces the regular link with an autolink.
[1]: <https://spec.commonmark.org/0.31.2/#links>
[2]: <https://spec.commonmark.org/0.31.2/#autolinks>