update apt cache after adding java 8 repo to apt
otherwise the install fails because it can't fine
oracle java.

Change-Id: I372b09e3319f8c3e612a8029b38bae4eb7b5213b
diff --git a/roles/java8-oracle/tasks/main.yml b/roles/java8-oracle/tasks/main.yml
index 9397fff..46deb76 100644
--- a/roles/java8-oracle/tasks/main.yml
+++ b/roles/java8-oracle/tasks/main.yml
@@ -1,7 +1,7 @@
 ---
 - name: Install add-apt-repostory
   become: yes
-  apt: name=software-properties-common state=latest
+  apt: name=software-properties-common state=latest update_cache=yes
 
 - name: Add Oracle Java Repository
   become: yes