Remove remote-directory from publishing in api-jobs

Since we set already target, there's no need to set remote-directory for
the api-quick-start job.

Also, setting it to empty is a noop for openstack-api-ref.

Btw. these two occurences are the only two occurences of
remote-directory in the directory.

Change-Id: Ib1185b3eff429f880b5fef8ea2c77135547b758c
Related-Bug: #1256828
Merge "Remove remote-directory from publishing in api-jobs"