CI: Switch from rbac to normal job

We enforced new defaults in [1], these jobs are identical.

[1]: https://review.opendev.org/c/openstack/magnum/+/876823

Needed-By: https://review.opendev.org/c/openstack/magnum-tempest-plugin/+/911095
Change-Id: Iebfef3c3454307358dfafd3250a484440f2ee565

Author: mnasiadka

.zuul.yaml

@@ -100,13 +100,13 @@
       - release-notes-jobs-python3
     check:
       jobs:
-        - magnum-tempest-plugin-tests-api-rbac
+        - magnum-tempest-plugin-tests-api
         - magnum-tempest-plugin-tests-cluster-k8s_fcos_v1-1.27-flannel
         - magnum-tempest-plugin-tests-cluster-k8s_fcos_v1-1.27-calico
         - magnum-container-build
     gate:
       jobs:
-        - magnum-tempest-plugin-tests-api-rbac
+        - magnum-tempest-plugin-tests-api
     post:
       jobs:
         - magnum-container-publish