The ASIOSession constructor catches all exceptions that aren't DBException or asio::system_error and changes them to an error code 50797. At a level higher up, all DBExceptions get swallowed without action. By doing this, we're essentially hiding all exceptions that come out of trying to construct an ASIOSession.

This ticket is to try unpeeling that catch-all, and do a few Evergreen passes to see if anything breaks. If not, then we should commit the removal to master for better debuggability in the future.