Set success-url on coverage jobs to cover/
Set success-url on coverage jobs to cover/

We fetch the coverage reports into the cover directory on logs. The
coverage report is the main thing you want to look at from a coverage
job. Set the url to that.

Change-Id: I387f01557afc36fd621197e2a97500ef44d7aace

openstack-infra/openstack-zuul-jobs,openstack-infra/openstack-zuul-jobs