catch exception for system_views also

catch exception for system_views also

Fixed yet another regression in SQL Server isolation level fetch (see
:ticket:`8231`, :ticket:`8475`), this time with "Microsoft Dynamics CRM
Database via Azure Active Directory", which apparently lacks the
``system_views`` view entirely. Error catching has been extended that under
no circumstances will this method ever fail, provided database connectivity
is present.

Fixes: #8525
Change-Id: I76a429e3329926069a0367d2e77ca1124b9a059d
(cherry picked from commit 0ee7d693b805c0f1aea0da5ebc11ea6e52b42c71)