scripts/device-crash-test: simplify Exception handling

We don't need to handle KeyboardInterruptError specifically; we can
instead tighten the scope of the broad Exception handlers to only catch
"Exception", which has the effect of allowing all BaseException classes
that do not inherit from Exception to be raised through.

KeyboardInterruptError and a few other important ones are
BaseExceptions, so this does the same thing with less code.

Signed-off-by: John Snow <jsnow@redhat.com>
Reported-by: Thomas Huth <thuth@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Message-id: 20211111143719.2162525-4-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>