Remove unused fedora-30 job
Remove unused fedora-30 job

We don't seem to be using this job anymore and fedora-30 is EOL. Lets
delete the job.

Change-Id: Id3030488625179b6bf4e186fcd8953ff8d6a578c

switch-ch/diskimage-builder,switch-ch/diskimage-builder,openstack/diskimage-builder,openstack/diskimage-builder