[3.12] gh-98963: Restore the ability to have a dict-less property. (GH-105262) (...

[3.12] gh-98963: Restore the ability to have a dict-less property. (GH-105262) (#105297)

gh-98963: Restore the ability to have a dict-less property. (GH-105262)

Ignore doc string assignment failures in `property` as has been the
behavior of all past Python releases.  (the docstring is discarded)
(cherry picked from commit 418befd75d4d0d1cba83d8b81e1a7bcc9a65be8e)

This fixes a behavior regression in 3.12beta1 where an AttributeError was being raised in a situation it has never been in the past. It keeps the existing unusual single situation where AttributeError does get raised.

Existing widely deployed projects depend on this not raising an exception.

Co-authored-by: Gregory P. Smith <greg@krypto.org>