Add the trivial job in the experimental pipeline

Change-Id: I3610ca9283debcd3d70b07ae147b944e8036efce
diff --git a/zuul.d/sp-cinder.yaml b/zuul.d/sp-cinder.yaml
index bd449a7..296b11b 100644
--- a/zuul.d/sp-cinder.yaml
+++ b/zuul.d/sp-cinder.yaml
@@ -6,3 +6,10 @@
     required-projects:
       - config
     timeout: 3600
+
+- project:
+    name: config
+    experimental:
+      jobs:
+        - sp-trivial-storprep:
+            branches: master