[3.12] gh-84443: SSLSocket.recv_into() now support buffer protocol with itemsize != 1 (GH-20310) (GH-112458)

It is also no longer use __len__().

(cherry picked from commit 812360fddda86d7aff5823f529ab720f57ddc411)

Co-authored-by: Zackery Spytz <zspytz@gmail.com>
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>