P1901 R2 Enabling the Use of weak_ptr as Keys in Unordered Associative Containers

[wg21bot]

P1901R0 Enabling the Use of weak_ptr as Keys in Unordered Associative Containers (Daryl Haresign)

[tituswinters]

Reviewed in Prague.

Forward to LWG for C++23.
Unanimous consent

(Will be moved to LWG at the beginning of Varna.)

[wg21bot]

P1901R1 Enabling the Use of weak_ptr as Keys in Unordered Associative Containers (Daryl Haresign)