Switch project-config to promote jobs [5]: Update specs, cleanup

The file lists for the project-config build jobs for docs-index and
specs-site are now in project-config, so remove the duplicate here.

Switch publishing for specs sites to the new promote job.

Needed-By: https://review.opendev.org/682216
Depends-On: https://review.opendev.org/682214
Change-Id: I3bb41238ebf84328049fd9fd5659594dcef69393

zuul.d/jobs.yaml

@@ -1057,11 +1057,6 @@
     vars:
       tox_envlist: specs
       sphinx_build_dir: specs
-    files:
-      - bindep.txt
-      - specs/.*
-      - other-requirements.txt
-      - tox.ini
 
 - job:
     name: project-config-dib
@@ -1085,11 +1080,6 @@
     vars:
       tox_envlist: infra-docs
       sphinx_build_dir: docs-site
-    files:
-      - bindep.txt
-      - docs-site/.*
-      - other-requirements.txt
-      - tox.ini
 
 - job:
     name: project-config-build-openafs-centos

zuul.d/project-templates.yaml

@@ -1075,16 +1075,17 @@
 - project-template:
     name: openstack-specs-jobs
     description: |
-      Runs jobs to build and publish documents for a specs repository.
+      Runs jobs to build documents for a specs repository and publishes the
+      result using a promote job.
     check:
       jobs:
         - openstack-tox-docs
     gate:
       jobs:
         - openstack-tox-docs
-    post:
+    promote:
       jobs:
-        - publish-openstack-specs
+        - promote-openstack-specs
 
 - project-template:
     name: build-only-specs-jobs