migrate to victoria testing runtime

As per victoria cycle testing runtime and community goal[1]
we need to migrate upstream CI/CD to Ubuntu Focal(20.04)
and Node.js 10.

Story: #2007865
Task: #40212

[1] https://governance.openstack.org/tc/goals/selected/victoria/migrate-ci-cd-jobs-to-ubuntu-focal.html

Change-Id: Idf991b9e4b3d52f5ca2c4157440341d1c9920fd6

.zuul.yaml

@@ -1,3 +1,3 @@
 - project:
     templates:
-      - nodejs4-jobs
+      - nodejs10-jobs