SID_CPDAG does not automatically converts a DAG to CPDAG

[xwshen51]

In cdt.metrics.SID_CPDAG, the prediction is not converted to a CPDAG. Currently one needs to convert a DAG to a CPDAG before inputting it to the function.

It may be better to add predictions = get_CPDAG(predictions) as done in SHD_CPDAG.

Thanks for your great contribution!

[diviyank]

Hello ! Whoops ! Yes we should do this step before, thanks for the feedback !