Add blurb.

Author: ZeroIntensity

Misc/NEWS.d/next/Library/2025-08-09-08-53-32.gh-issue-137583.s6OZud.rst

@@ -0,0 +1,4 @@
+Fix a deadlock introduced in the :mod:`ssl` module when a call to
+:class:`~ssl.SSLSocket.recv` was blocked in one thread, while another
+attempted to call :class:`~ssl.SSLSocket.send` to unblock it in another
+thread.