Move ceph job to voting

Currently ceph job is n-v, if I remember
correctly it was kept n-v due to its stability.

But it is stable and voting on many projects. With
n-v it is hard to monitor it all the time.

let's make it voting and if any new tests failing we
can add that in the ceph blacklist in advance.
Example: https://review.opendev.org/#/c/724866/

Change-Id: Ic484d233b325c887f0a19f3ec06376d403beb964
diff --git a/.zuul.yaml b/.zuul.yaml
index 09a5897..4ed9d2d 100644
--- a/.zuul.yaml
+++ b/.zuul.yaml
@@ -673,7 +673,6 @@
             voting: false
             irrelevant-files: *tempest-irrelevant-files
         - devstack-plugin-ceph-tempest-py3:
-            voting: false
             irrelevant-files: *tempest-irrelevant-files
         - neutron-grenade-multinode:
             irrelevant-files: *tempest-irrelevant-files
@@ -715,6 +714,8 @@
             irrelevant-files: *tempest-irrelevant-files
         - tempest-ipv6-only:
             irrelevant-files: *tempest-irrelevant-files-2
+        - devstack-plugin-ceph-tempest-py3:
+            irrelevant-files: *tempest-irrelevant-files
     experimental:
       jobs:
         - tempest-cinder-v2-api: