Cycle topology bug with default configuration.

[GoncaloBFM]

AMLSim generates a "cycle" money laundering topology with the default configuration where the last node doesn't connect to the first node resulting in the following subgraph that isn't a cycle:

1303 -> 626 -> 130 -> 397 -> 180 -> 485 -> 945
(values above are account ids)

slice of alert_transactions.csv referencing the cycle:

alert_id,alert_type,is_sar,tran_id,orig_acct,bene_acct,tx_type,base_amt,tran_timestamp
8,cycle,True,75415,130,397,TRANSFER,164.33,2017-12-12T00:00:00Z
8,cycle,True,75594,626,130,TRANSFER,777.07,2017-12-13T00:00:00Z
8,cycle,True,75696,485,945,TRANSFER,108.68,2017-12-14T00:00:00Z
8,cycle,True,75819,180,485,TRANSFER,476.06,2017-12-15T00:00:00Z
8,cycle,True,75820,1303,626,TRANSFER,706.21,2017-12-15T00:00:00Z
8,cycle,True,76060,397,180,TRANSFER,459.01,2017-12-16T00:00:00Z