Enable Org-wide discussions and disable Team Discussions

[ovflowd]

GitHub is sunsetting team-based discussions in favour of org-wide discussions which is GitHub Discussions.

I'd like to suggest for us to:

• Create Org-wide discussions and configure them (e.g., categories and stuff)
• Disable Team-based discussions as they always had poor visibility.
• Move relevant discussions that are still open to the org-wide discussions (GitHub has a built-in feature for moving this).

Org-wide Discussions will give us a better reach when making announcements or when we want to have essential discussions involving the Community. I see it as a great place for us to:

• Post relevant announcements to contributors
• Post relevant announcements to our community/user-base (such as security releases)
• Post relevant discussions/threads for new features, or upcoming critical changes

Regardless of the points above regarding what we could use the org-wide discussions for, this issue asks to, for now, enable org-wide discussions and, if the TSC is okay with it, disable team-based ones.

cc @nodejs/tsc

[nschonni]

Duplicate of #679
Team discussions thread nodejs/TSC#1340