pytest: fix test_you_forgot_closed_channel() closing assumption.

Since we now time out connections more gently, we can race: make sure
we want for them to disconnect.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

tests/test_closing.py

@@ -3446,9 +3446,10 @@ def test_you_forgot_closed_channel(node_factory, executor):
     wait_for(lambda: only_one(only_one(l2.rpc.listpeers()['peers'])['channels'])['state'] == 'CLOSINGD_COMPLETE')
     assert only_one(only_one(l1.rpc.listpeers()['peers'])['channels'])['state'] == 'CLOSINGD_SIGEXCHANGE'
 
+    # l2 closes on us.
+    wait_for(lambda: only_one(l1.rpc.listpeers()['peers'])['connected'] is False)
+
     # l1 reconnects, it should succeed.
-    if only_one(l1.rpc.listpeers(l2.info['id'])['peers'])['connected']:
-        l1.rpc.disconnect(l2.info['id'], force=True)
     l1.rpc.connect(l2.info['id'], 'localhost', l2.port)
     fut.result(TIMEOUT)