No such method Exception::getText()

No such method Exception::getText()

It looks like a recent change converted this try/catch
statement from MWException to Exception, unfortunatly it
is still calling a method that only exists on MWException.

We arn't doing anything with the exception but exiting.  Lets
just allow the exception to be uncaught and fail naturally. The
uncaught exception will still output an error and return
a non-0 exit code.

Change-Id: I3e0e9d283c255d2aba8139d675943e93d7cb021a