[stable-only] Remove glance-code-constants-check

This job is only useful in the development branch; there's no
point in running it in the stable branches.

Change-Id: If36e64b61767dc5c1df0daec2dd176fecd409926
(cherry picked from commit 06a9228809)
(cherry picked from commit 5fbf47378e)
(cherry picked from commit 3cfbb69c01)
(cherry picked from commit 1471384ce9)
(cherry picked from commit c9a0215e35)
(cherry picked from commit 7ffbbebd88)

.zuul.yaml

@@ -17,24 +17,6 @@
       - ^tox.ini$
       - ^\.zuul\.yaml$
 
-- job:
-    name: glance-code-constants-check
-    parent: tox
-    description: |
-      Tests to catch when code constants have gotten out of sync.
-    vars:
-      tox_envlist: gateonly
-    irrelevant-files:
-      - ^(test-|)requirements.txt$
-      - ^.*\.rst$
-      - ^api-ref/.*$
-      - ^doc/.*$
-      - ^etc/.*$
-      - ^releasenotes/.*$
-      - ^setup.cfg$
-      - ^tox.ini$
-      - ^\.zuul\.yaml$
-
 - job:
     name: glance-tox-oslo-tips-base
     parent: tox
@@ -220,7 +202,6 @@
         - openstack-tox-functional-py37
         - glance-eventlet-ssl-handshake-broken-py3:
             voting: false
-        - glance-code-constants-check
         - devstack-plugin-ceph-tempest:
             voting: false
             irrelevant-files: &tempest-irrelevant-files