Add nodejs v20 project templates for 2024.1 release

This commit defines the nodejs v20 job template so that horizon
and all its plugins can use this template to run nodejs jobs with
nodejs v20 which is the testing runtime for 2024.1 release[1].

[1] https://review.opendev.org/c/openstack/governance/+/900224

Change-Id: I47a89078dd70da58f95c09eea23ec00a69b5b268

zuul.d/project-templates.yaml

@@ -3217,6 +3217,31 @@
               node_version: 18
             nodeset: ubuntu-jammy
 
+- project-template:
+    name: nodejs20-jobs
+    description: |
+      Run lint and test jobs using Node 20.
+    check:
+      jobs:
+        - nodejs-run-lint:
+            vars:
+              node_version: 20
+            nodeset: ubuntu-jammy
+        - nodejs-run-test-browser:
+            vars:
+              node_version: 20
+            nodeset: ubuntu-jammy
+    gate:
+      jobs:
+        - nodejs-run-lint:
+            vars:
+              node_version: 20
+            nodeset: ubuntu-jammy
+        - nodejs-run-test-browser:
+            vars:
+              node_version: 20
+            nodeset: ubuntu-jammy
+
 - project-template:
     name: nodejs4-docs
     description: |
@@ -3311,6 +3336,21 @@
             vars:
               node_version: 18
 
+- project-template:
+    name: nodejs20-docs
+    description: |
+      Run docs jobs using Node 20
+    check:
+      jobs:
+        - nodejs-run-docs:
+            vars:
+              node_version: 20
+    gate:
+      jobs:
+        - nodejs-run-docs:
+            vars:
+              node_version: 20
+
 - project-template:
     name: tempest-plugin-jobs
     description: |