Use templates for cover and lower-constraints

Use openstack-tox-cover template, this runs the cover job
in the check queue only.

Use openstack-lower-constraints-jobs template.

Remove jobs that are part of the templates.

Change-Id: I276ef74f5ca9f2be7b0f03f19dca897390cbe105

.zuul.yaml

@@ -1,27 +1,25 @@
 - project:
     templates:
+      - check-requirements
+      - openstack-cover-jobs
+      - openstack-lower-constraints-jobs
       - openstack-python-jobs
       - openstack-python35-jobs
       - openstack-python36-jobs
-      - check-requirements
     check:
       jobs:
         - monasca-tempest-python-influxdb
         - monasca-tempest-java-influxdb
         - monasca-tempest-python-cassandra
         - monasca-tempest-java-cassandra
-        - openstack-tox-lower-constraints
         - legacy-monasca-persister-maven-build
-        - openstack-tox-cover
     gate:
       jobs:
         - monasca-tempest-python-influxdb
         - monasca-tempest-java-influxdb
         - monasca-tempest-python-cassandra
         - monasca-tempest-java-cassandra
-        - openstack-tox-lower-constraints
         - legacy-monasca-persister-maven-build
-        - openstack-tox-cover
     post:
       jobs:
         - legacy-monasca-persister-localrepo-upload