Missing audit event when registering a callback function in `sys.monitoring`.

[markshannon]

PEP 669 states that "Registering or unregistering a callback function will generate a sys.audit event.", but it isn't implemented yet.

Linked PRs

• GH-107774: Add missing audit event for PEP 669 #107775
• [3.12] GH-107774: Add missing audit event for PEP 669 (GH-107775) #107839

[hugovk]

Thanks!