The code to workaround the intermittant error didn't work,
and we finally hit it again:
```
# If reject happens fast enough, connect fails with "disconnected
# during connection"
try:
l3.connect(l1)
except RpcError as err:
> assert "disconnected during connection" in err.error
E assert 'disconnected during connection' in {'code': 402, 'message': 'disconnected during connection'}
E + where {'code': 402, 'message': 'disconnected during connection'} = RpcError("RPC call failed: method: connect, payload: {'id': '0266e4598d1d3c415f572a8488830b60f7e744ed9235eb0b1ba93283b315c03518', 'host': '127.0.0.1', 'port': 41865}, error: {'code': 402, 'message': 'disconnected during connection'}").error
```
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
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