Remove fedora28 from redhat-8 test

Change-Id: I6e9fabe859e546447695e5fb31f870d6bb375f06

tripleo_ansible/roles/test_deps/vars/redhat-8.yml

@@ -15,13 +15,10 @@
 # under the License.
 
 
-test_deps_repo: https://trunk.rdoproject.org/fedora/current
+test_deps_repo: https://trunk.rdoproject.org/redhat8-master/current
 test_deps_selinux_packages:
   - python3-libselinux
 test_deps_tripleo_packages:
   - python3-tripleoclient
   - python3-openstacksdk
 test_deps_tripleo_repos: current-tripleo
-
-# TODO(cloudnull): when RDO has centos8 repos remove this.
-test_deps_repo_version: fedora28-master