Change About IDLE to direct discussions to discuss.python.org. Users are already doing so.

Currently,idle-dev@python.org and idle-dev mailing list serve, 90+%, to collect spam. The few user messages per year are off topic requests for help, mostly not about IDLE. The email should be disabled and the mailing list archived, but these actions are not part of this tracker.

Linked PRs

• GH-122482: Make About IDLE direct discussion to DPO #122483
• [3.13] GH-122482: Make About IDLE direct discussion to DPO (GH-122483) #122485
• [3.12] GH-122482: Make About IDLE direct discussion to DPO (GH-122483) #122486