Make py33 job voting in check and gate for Rubick

Rubick project is now passing tests in py33 env consistently, so
make this job voting in check and gate pipelines for the project.

Change-Id: I8849dc95dbae6e0ad84746ab461188906f507c32

modules/openstack_project/files/zuul/layout.yaml

@@ -639,8 +639,6 @@ jobs:
     voting: false
   - name: gate-refstack-python33
     voting: false
-  - name: gate-rubick-python33
-    voting: false
   - name: ^(gate|check)-sqlalchemy-migrate-devstack-dsvm$
     voting: false
   - name: gate-manila-pylint
@@ -4513,6 +4511,7 @@ projects:
     gate:
       - gate-rubick-pep8
       - gate-rubick-python27
+      - gate-rubick-python33
     post:
       - rubick-coverage