nova-next: Deploy noVNC from source instead of packages

To help improve early detection of issues with newer noVNC releases the
nova-next job now deploys directly from source.

Depends-On: https://review.opendev.org/c/openstack/devstack/+/816736

Change-Id: Ic14d2b13cbf0369fc752d457d73d65488e6df3f9

.zuul.yaml

@@ -191,10 +191,13 @@
       Starting in Train, the job enabled counting quota usage from placement.
       Starting in Ussuri, the job was changed to multinode.
       Starting in Wallaby, the job defaults to the q35 machine type.
+      Starting in Yoga, the job tests noVNC from source.
       Runs all tempest compute API and most scenario tests concurrently.
     irrelevant-files: *nova-base-irrelevant-files
     # Run post-tempest tests like for nova-manage commands.
     post-run: playbooks/nova-next/post.yaml
+    required-projects:
+        - novnc/novnc
     vars:
       # We use the "all" environment for tempest_test_regex and
       # tempest_exclude_regex.
@@ -265,6 +268,8 @@
         ENABLE_VOLUME_MULTIATTACH: True
         # Added in Ussuri.
         FORCE_CONFIG_DRIVE: True
+        # Added in Yoga.
+        NOVNC_FROM_PACKAGE: False
       devstack_services:
         # Disable OVN services
         br-ex-tcpdump: false
@@ -297,6 +302,8 @@
           NOVA_USE_SERVICE_TOKEN: True
           NOVA_CONSOLE_PROXY_COMPUTE_TLS: True
           FORCE_CONFIG_DRIVE: True
+          # Added in Yoga.
+          NOVNC_FROM_PACKAGE: False
         devstack_services:
           # Disable OVN services
           br-ex-tcpdump: false