update the nightly build to set the passwords to defaults

Change-Id: I3bc09be892bb8127cdca84a9412a349559316c7f
diff --git a/config/onlab_develop_pod.yml b/config/onlab_develop_pod.yml
index 6d72075..bbe2b5e 100644
--- a/config/onlab_develop_pod.yml
+++ b/config/onlab_develop_pod.yml
@@ -28,6 +28,11 @@
   external_gw: '10.90.0.1'
   skipTags:
 
+passwords:
+  compute_node: "ubuntu"
+  maas_admin: "admin"
+  maas_user: "cord"
+
 docker:
   imageVersion: candidate