Frequently discarding old build for jobs that take up a lot of space

Change-Id: Ib3004ae6ad270648750301eb2cb8fb50b56620e2
diff --git a/jjb/cord-test/nightly-build-pipeline.yaml b/jjb/cord-test/nightly-build-pipeline.yaml
index b697b73..c81b093 100644
--- a/jjb/cord-test/nightly-build-pipeline.yaml
+++ b/jjb/cord-test/nightly-build-pipeline.yaml
@@ -10,8 +10,8 @@
 
     properties:
       - cord-infra-properties:
-          build-days-to-keep: 30
-          artifact-num-to-keep: 15
+          build-days-to-keep: '{big-build-days-to-keep}'
+          artifact-num-to-keep: '{big-artifact-num-to-keep}'
 
 
 - job-template: