logging.Handler.lock should actually be threading.RLock

[gsnedders]

We have:

https://github.com/python/typeshed/blob/614e9499f145e9dccade16d906247276f1d5e6aa/stdlib/logging/__init__.pyi#L249C11-L249C25

However, the stdlib actually uses an RLock (and has done since CPython 2.5, python/cpython@4a70486):

https://github.com/python/cpython/blob/7dc41ad6a7826ffc675f088972de96624917696e/Lib/logging/__init__.py#L961

Note that RLock is not a subclass of Lock.

See also #13381 (Should logging.Handler.lock allow None?)

[JelleZijlstra]

PR welcome!