Add opendev nox docs promotion

This adds a new publish-opendev-nox-docs project-template which will run
opendev-nox-docs and opendev-promote-docs (with the appropriate var for
nox jobs set) to promote and publish our docs using nox based jobs.

Change-Id: I7ed1f439062f13a15fd5a24fbb77d4135cfb08ee

zuul.d/project-templates.yaml

@@ -26,3 +26,34 @@
     promote:
       jobs:
         - opendev-promote-docs
+
+- project-template:
+    name: build-opendev-nox-docs
+    description: |
+      Build documentation with "nox".
+    check:
+      jobs:
+        - opendev-nox-docs
+    gate:
+      jobs:
+        - opendev-nox-docs
+
+- project-template:
+    name: publish-opendev-nox-docs
+    description: |
+      Build and publish documentation with "nox".
+
+      The documents that are build in the "gate" pipeline
+      are published via a promote job to
+      https://docs.opendev.org/{{ zuul.project.name }}.
+    check:
+      jobs:
+        - opendev-nox-docs
+    gate:
+      jobs:
+        - opendev-nox-docs
+    promote:
+      jobs:
+        - opendev-promote-docs:
+            vars:
+              download_artifact_job: opendev-nox-docs