Require a base job

This makes base jobs required and allows for a per-tenant default.

Story: 2001110
Task: 4793
Change-Id: I26ffddad8358c156cfac749ce98af70f3447f671
diff --git a/tests/fixtures/layouts/footer-message.yaml b/tests/fixtures/layouts/footer-message.yaml
index e500371..4ee25f6 100644
--- a/tests/fixtures/layouts/footer-message.yaml
+++ b/tests/fixtures/layouts/footer-message.yaml
@@ -26,6 +26,10 @@
     precedence: high
 
 - job:
+    name: base
+    parent: null
+
+- job:
     name: project-test1
 #    success-url: http://logs.exxxample.com/{change.number}/{change.patchset}/{pipeline.name}/{job.name}