gh-128002: fix tsan race in closing socket in test_sslproto (#131399)

Lib/test/test_asyncio/functional.py

@@ -217,16 +217,15 @@ def stop(self):
                     pass
         finally:
             super().stop()
-
-    def run(self):
-        try:
-            with self._sock:
-                self._sock.setblocking(False)
-                self._run()
-        finally:
+            self._sock.close()
             self._s1.close()
             self._s2.close()
 
+
+    def run(self):
+        self._sock.setblocking(False)
+        self._run()
+
     def _run(self):
         while self._active:
             if self._clients >= self._max_clients: