[3.12] bpo-26791: Update shutil.move() to provide the same symlink move behavior as the mv shell when moving a symlink into a directory that is the target of the symlink (GH-21759) (GH-113517)

(cherry picked from commit c66b577d9f7a11ffab57985fd6fb22e9dfd4f245)

Co-authored-by: Jeffrey Kintscher <49998481+websurfer5@users.noreply.github.com>