bpo-45129 Remove deprecated reuse_address (GH-28207)

Due to significant security concerns, the reuse_address parameter of
asyncio.loop.create_datagram_endpoint, deprecated in Python 3.9, is
now removed. This is because of the behavior of the socket option
SO_REUSEADDR in UDP.

Co-authored-by: Łukasz Langa <lukasz@langa.pl>