We reconnect from l3->l2, but l2 is also trying to reconnect and
we can race:
```
# Now try when l3 uses scid for entry point of blinded path.
l3.stop()
l3.daemon.opts['dev-invoice-bpath-scid'] = None
l3.start()
> l3.rpc.connect(l2.info['id'], 'localhost', l2.port)
tests/test_pay.py:5667:
...
> raise RpcError(method, payload, resp['error'])
E pyln.client.lightning.RpcError: RPC call failed: method: connect, payload: {'id': '022d223620a359a47ff7f7ac447c85c46c923da53389221a0054c11c1e3ca31d59', 'host': 'localhost', 'port': 33557}, error: {'code': 402, 'message': 'disconnected during connection'}
```
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
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