This is almost certainly because the HTLCs are not fully settled, so wait for that:
```
2023-06-20T11:37:56.2332158Z assert apys_2[0]['our_start_balance_msat'] == Millisatoshi(0)
2023-06-20T11:37:56.2332443Z > assert apys_1[0]['routed_out_msat'] == apys_2[0]['routed_in_msat']
2023-06-20T11:37:56.2332571Z E assert 1892216msat == 2810170msat
2023-06-20T11:37:56.2332580Z
2023-06-20T11:37:56.2332717Z tests/test_pay.py:81: AssertionError
```
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>