Scoped exceptions in DaVinci configuration code

Issue found discussing a user misleading error message, see https://mattermost.web.cern.ch/lhcb/pl/oqmbwnzn6pn5udb5um4tui4fcc.

In short one should never use bare except statements as in https://gitlab.cern.ch/lhcb/DaVinci/-/blob/master/Phys/DaVinci/python/DaVinci/algorithms.py#L217-223. There are several places to be fixed. In this particular example an ImportError and/or ModuleNotFoundError should be added.