Alter config format to lists of dictionaries

Rather than the previous dictionary of lists.

Change-Id: I0f8ffba15da489da097b14388699685f22b0579f
diff --git a/tests/fixtures/config/multi-tenant/common.yaml b/tests/fixtures/config/multi-tenant/common.yaml
index 8fc3bba..6014227 100644
--- a/tests/fixtures/config/multi-tenant/common.yaml
+++ b/tests/fixtures/config/multi-tenant/common.yaml
@@ -1,5 +1,5 @@
-pipelines:
-  - name: check
+- pipeline:
+    name: check
     manager: independent
     source:
       gerrit