Show result of the daily bugzilla cron job only in the error case

If you get daily the mail

 test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.daily )

then you may want to edit /etc/cron.daily/bugzilla3 and uncomment with # the following lines:

 set -e
 set -x

These do tracing and check of error code check