[bnporc] Add try/except on old BNP website request to prevent error 500

Sometimes the request to the old website returns a Server Error (500)
that crashes all BNP connections.
With this try/except , the connection to the old website will fail but
it will not prevent all the accounts from the new API to be scraped
correctly.

Closes: 7735@zendesk, 7863@zendesk, 27832@Sibi, 16333@Sibi, 27833@Sibi