updated reference to file for target env.

update_cache.yml

diff --git a/update_cache.yml b/update_cache.yml
index 754e9e4..8c866d3 100644
--- a/update_cache.yml
+++ b/update_cache.yml
@@ -1,7 +1,7 @@
 ---
 - hosts: planet
   vars_files:
-  - ~/.apigee/credentials.yml
+  - /tmp/apigee-workspace/apigee/credentials.yml
   pre_tasks:
   - setup:
   - ec2_facts: