test: skip pause/resume test on python 3.13 and greater

Accounting in asyncio.DatagramTransport is broken, so this won't pass.
python/cpython#135444
python/cpython#135445

Author: jsbronder

test/test_aio.py

@@ -393,6 +393,7 @@ async def test_unconnected_sender(addr: _Address) -> None:
     connected.close()
 
 
+@pytest.mark.skipif(sys.version_info >= (3, 13), reason="https://github.com/python/cpython/issues/135444")
 @pytest.mark.asyncio
 async def test_protocol_pause_resume(
     monkeypatch: pytest.MonkeyPatch,